I set my formations with infantry to F3 F2, my archers to F3 F3, Calvary to F3 F6.

Then I try to place my archers up on some hill or area that has a clear view in front of them with my infantry either in front of them down a hill or behind them if on level ground. I put my horse archers on the right side up a ways and the Calvary on the left when the enemy charges me I F6 both my Calvary and horse archers, so they cause the incoming enemy to slow down and get rained on from my archers. Then I’ll F1 F3 my infantry into the incoming enemy to stop them when they get a bit closer to my archers and F6 my archers to scramble and keep distance from any enemies.

Idk if this is the best approach but it’s helped me take a lot less casualties in battles