Here's a fun tip for BEGINNERS.

To minimise microing, group them base on type. ie, same archers with spears, loan swords with elite swords and all cav together. Your general can be part of any one of this group. (to group units, select any units you want to group together and press "g")

This way, you have a group of archers protected by spears to engage in missile fights, a second group of melee infantry held ready for the main action and a third group consist of cav to distract or raid the enemy lines.

This will help you execute your plan easier should there be any sudden changes with little worry of clicking the entire formation into action and sending wrong units into the fray.

Play around with the default formation for each group for easier control.