Always use terrain features wisely as it could be a matter of life and death for your army.
Place your archers onto of hills or cliffs, place your cannons in the same place as archers but have them closely guarded by some infantry/cavalry that are not going to be used much.
Try and sneak up behind the enemy archers by using trees and other terrain features as they cannot see you (around 50/50 chance of them not sighting you...just depends on how careful you are)
We have more cheats and tips for this game here, Dark Omen Warhammer cheats
Comments for this hint