Im not that GREAT of a player, but im not dumb either

1 - Always start exploring with your scout around your town, then try to find enemy towns 2 - When making defensive buildings(walls, towers, gates and castles) Always leave an area in your town so you can build stuff.
In each "segment" of a wall, place a gate to provide easier access to your city.
Always fill your towers with archers, so they can fire more then 1 arrow at a time.

3 - Start creating your archery and infantry at the feudal age, calvary can be made later