Well, perfect micro is when you never have an idle villager, every unit is attacking its counter, you're raiding all the enemy resources, etc. Realistically, you can't have perfect micro, but just try to have as little idle villie time as possible (I like to set the "find idle villager" key to space, and just absently press that when I'm busy), try to have every unit attack its counter, and try to raid the enemy resources (particularly gold) as much as possible.
If you go to www.aotsanctuary.com,you can find expert recorded games of the god of your choosing. Just observe how seldom they have a villager doing nothing, and how well they can raid/attack while keeping up a good economy. (usually, even when mounting a large attack mid-game, they're still micro-ing their eco half the time. Most people get caught up in the battle and neglect their eco)And, to get better, simply practice. A lot. There's really no easy way or technique to improve micro, other than playing online and playing random maps.
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