Once you start getting a build up of tools put a Colonist in the Armoury to build up a supply of muskets. These can be used to rearm routed and captured troops quickly as well as to raise a militia. If you have Paul Revere in Congress a militia will be raised automatically. Also excess muskets can be used to arm your Indian Allies or be sold in Europe where they always fetch a good price. Muskets may also be captured by privateers or when you capture a Colony. Muskets can be bought cheap in Europe at the beginning of the game but they some become prohibitively expensive and must be acquired by other means. It's a good idea to buy 100 at the beginning of the game at 200 or 300 to arm you first soldiers.
Horses are ALWAYS in demand. Dragoons are easily routed and need horses to rearm. Horses are more difficult to make than other commodities as you only get them if you have an excess food supply in your Colony. Half the food goes to population growth and half to horse growth, rounded up. The more horses you have the faster they breed, also a stable will double breeding capacity BUT you must have enough food, so plow the land and get expert Farmers and Fishermen (presumably the Colonists eat fish leaving the folder for the horses). Of course more horse growth means more population growth, which you may not want - once the warehouses are full population growth will double, so you may want to move a Farmer or Fisherman temporarily to another job. Build all three warehouses so you have plenty of room to store them for when a War starts.
Once Horses have reached capacity move excess Farmers / Fishermen to other duties, you might even want to produce a little less than the required amount of Food, living of the previously created surpluses in your Warehouse. This will reduce population growth.
During the revolution you might want to have a galleon in each port full up with horses, as the demand is so great. Horses may also be captured by privateers or when you capture a Colony. Horses can be bought in Europe, their price usually tops out at about 900. It is a good idea to arm any soldiers you receive in Europe with horses there, so they are ready to fit when they arrive and don't deplete Colonial stocks. Horses can be shipped over but only if you really need them as they are so expensive and you may have to run a blockade.
Move Muskets and Horses to where they are needed
Have a spare Wagon Train standing by so that when one Colonies warehouses become full up, the muskets and horses can be moved to a less full one. This may also increase horse breeding capacity in the other Colony. Also move them to the front line where they will be in high demand. Privateers can be used to move them between land masses as they are so fast. Consult your Economic Advisor to find out where surpluses are.
Fortify Veteran Dragoons on Mountains outside your Colonies
If an enemy Dragoon Fortifies on a Mountain square (+200% Defence!) outside one of your Colonies it will be very difficult to remove, and will cost you a lot of damaged or destroyed units. Also your ore supply may be disrupted meaning you can't make tools, meaning you can't construct weapons and complex buildings. If you have a spare Dragoon keep him permanently on this square, he will deny it to the enemy and cost them valuable troops trying to remove it. It is best to fortify next to your Colonies, as this protects your production, allows units to go back for refit immediately, and prevents capture and lose of Veteran status. If they are not attacked, fortify them on cleared land, which has a lower defence rating, making attack more likely.
DO NOT fortify if it is next to an Indian village as they will be continually attacked, let them attack your enemy instead, also the Indians receive the native ambush bonus so are very effective. If an enemy unit is fortified on a Mountain outside your Colony, don't use Artillery, instead fortify Veteran Dragoons outside next to the enemy, and they will be attacked. If they loose their horses don't move them as the will receive a 50% fortified bonus after the first turn. Also arm near by Indians and perhaps incite them to War. They may spontaneously attack on their own.
Capture disarmed Soldiers from Colony
If there is a disarmed Solder or Colonist outside your Colony, attack from in the Colony, then your Unit can be refitted immediately if it loses, and will be better defended. If the Colonist is a Pioneer, wait for it to found a Colony, then capture it and you will get a Colonist (Possibly Hardy Pioneer) and 100 Tools, otherwise he will be killed.
Ambush unprotected Artillery in the Open
Artillery is very vulnerable in the open (-75%), so send a Dragoon to get it. This is also good as your Indian Allies are not good at fighting Artillery and can lose a lot of villages to it. Also if a Colony has fortification this will further increases Artillery strength. Don't attack if it protected by Soldiers / Dragoons. Sometimes it may even be worth starting a War over just to get it.
Station a Dragoon in a Colony on founding
This guards again surprise raids, and gives time for reinforcements to arrive. Make sure you have a good road network. If there are no hostile units in the area downgrade the unit to a Soldier, thus leaving 50 horses in the warehouse. This will mean half the excess food will go into horse breeding, thus creating spare horses should the Dragoon get damaged in combat.
When you Capture a Colony...
Don't get the Colonists producing commodities as you will have to send Ships / Wagon Trains to get these. Instead, just make liberty bells. If there are horses there do some farming up to the horse breeding capacity, and you may get enough to rearm a damaged Dragoon or create a Scout. If not, don't bother and burn up some of the excess food, you will be warned if it gets too low. Also if you have a little off a commodity unprocessed and some processed, try and process it all, as it sells for more and takes up less holds. Trade Goods and excess Muskets can be sold to near by Indians at a fair profit, thus saving more holds.
Capture a Colony with a Scout
If a Colony is new it may only be defended with a Colonist. If you have a Scout near by attack and you may get the Colony. If you want to cheat, do a save first.
Soldier in the Armoury
If you have an unarmed Veteran Soldier in a Colony and some spare Tools, put him in the Armoury until he has made enough Muskets to rearm himself. It is better if you have an Magazine or Arsenal as he will be able to rearm faster.
Kill Power at Beginning
If you come across another Power at the beginning of the Game, build your first Colony next to it. Buy some Muskets, Horses and Artillery (these are all cheap at the beginning) and attack. You'll usually win as new Colonies are poorly defended, particularly the Spanish who are off beating up the Indians. The power will probably fatally weakened and may well cede its remaining territories in the Treaty of ... to another Power, and withdraw from the New World.
Spare Wagon Train
Have a spare Wagon Train to transport Muskets and Horses to the front and take away plunder. Make sure you have a good road network in place before you start the War, which will also get your Military Units there quicker with less chance of ambush. Surplus Lumber, Ore and Tools can also be moved to where they are in demand, particularly Tools as most building can't be built with out them, and smaller Colonies can't support an Iron Working Industry.
It can also be used as temporary storage if one commodities warehouse space becomes overloaded e.g. Tools while your building a Fortress requiring 200 Tools. The spare Wagon Train can also be used to start a trade route with a new / captured Colony immediately, giving you time to build another, and letting you get plunder out quickly in case it is re-taken. Remember you can't build more Wagon Trains than you have Colonies but they can be captured from other Europeans. Goods can be moved direct to Ships without going via a Warehouse.
If you don't have too many Tools, and want to raise a Pioneer, move the what you don't want to use into a spare Wagon Train or Ship Temporarily. Then move it back again after.
Peace then War
If you are at War with a Power and land an Invasion Force, they may sue for peace and offer you tribute. They will assume the treaty will hold and not attack your troops, raise new troops of their own or send re-enforcement's. Your can then attack next turn with a greater chance of victory. This of course is CHEATING and should not be allowed, as you suffer no penalties what so ever for this act of infamy.
Use your Scouts
It is a good idea to send a Scout into a Colony before you attack it, to see whether you stand a chance of winning, if not look for another target. The Scout may be lost, but if you do a save first you can try again. Also it uses all its movement points so it may be attacked next turn.
Build the highest Level of Fortification you can afford
Stockades give +50% defence, Forts +100% and Fortresses +200%. Enemy Dragoons usually attack no matter what the level of Fortification, and almost always loss against Fortresses. Also Forts and Fortresses will attack enemy ships in neighbouring squares, their chances are greater with more Artillery. If you have few troops in a Colony the enemy will always attack, its a bit risky but you can wipe out lots of their troops.
Don't upset the Indians
Don't Fortify outside Indian Villages. They will continually attack you and usually win due to the Indian Ambush Bonus. If they demand something give it to them, it will create good will and avoid a raid. The only exceptions are critical commodities in short supply ie. Food, Horses, Tools and Muskets. Indian Wars can last a long time and severely hamper plans for expansion, territory outside your Colonies becomes very unsafe. Building roads next to Indian villages angers them especially if you don't pay but makes trading with them easier which calms them down. This also allows your military units to move more freely as they can often become blocked by Indians if you don't have redundant roads.
Intervene to Save Indians
If an Indian Tribe looks like it is losing a War badly, particularly on your Continent, it may be a good idea to aid them in their War. Sell them Horses / Muskets up to 500, and declare War on the Power attacking them. Once they obtain decent weapons they will be able to capture more. Send your Veteran Dragoons to ambush unprotected Artillery (it can devastate Indian Villages), and round up disarmed Soldiers, so they don't fight again or get scalped by the Indians. You might also want to attack Non-Veteran Units before they get promoted. If the Indians do get wiped out, the full force of the enemy power will be directed against YOU.
Be careful when attacking a Colony if another Power is also attacking it
Generally the other Power will wait for you to use up your troops attacking the Colony, and when it is about to fall move in and take it. You will then either have lost all those troops for nothing, effectively having given them to the other Power, or have to then use more troops to attack the second Power, and fight two Powers simultaneously. The way to avoid this situation is to ensure you have a sufficiently large invasion force for the task. Also try and stir up the near by Indians.
If you have not yet contacted a Foreign Power and see one of its land units near one of your land units, you can move your unit away, and delay contact. With Hernando de Soto in Congress, all units have a sighting radius of 2 squares, making this easier to do. Generally, enemy troops don't start landing round your Colonies until contact has been made. So use this extra time wisely, by improving squares around your Colonies before they become blockaded, raising Garrisons, and increasing your levels of Fortification. One Hill or Mountain should have a road first, as Ore is essential, and enemy Units Fortify here more often. If cleared land can produce Ore, put a road through it, and plow it, so it can be used for Ore and Food production during a siege. Of course later contact may mean a higher tribute being demanded or no peace treaty at all. It's a bit of a gamble.
NEVER Pay Tribute to remove troops, increase your Garrison and Level of Fortification and let them destroy themselves in an assault. The money saved can be used to buy more Troops. If you pay, they go away and come back a couple of turns later, and will be able to buy a bigger Army with YOUR money. The only exception is when the terrain around Colonies has not been improved, if you pay, you can get a Hardy Pioneer in there quickly to increase productivity, so the Colony can build more Troops and Artillery. Put a road through Mountains first as enemies usually fortify there first, and it has a defence bonus of 200%, also Ore is always in short supply.
If your army is weak and a power demands Tribute, and has a lot of Units near your Colonies, PAY! Otherwise you will almost certainly lose one, which reduces your productive capacity and increases his, and it must also be re-taken ie. your getting a bargain by keeping the Peace. Then what you must do is increase the Level of Fortification of all Colonies, and raise a larger Army by buying Units in Europe if necessary, Artillery is very cheap at the beginning.