Some good stuff from sheets:

Steal blinds when they are worth something. Have a plan if called.
If you are a known player, your opponents may have a read of you from past play and therefore, your current playing style might not matter.
If you know how you are perceived, then you know how players will play at you.
If a player leaves chips behind so that they can fold, then they are probably on a resteal.
Middle game is usually determined by the amount of players left and stack sizes in relation to the blinds. When the majority of your opponents at your table has 10M. You can steal now.
When antes come into play, no more limping.
When you can add 10% to your stack you can steal.
If you are in the blinds with a 10M and a late position raiser has 10M, you can raise with a wide range for a resteal.
Players in the blinds with 15-10bbs are good targets to steal from. Even in any position that you might be in. Ex. bb has an 11bb stack and you are in mp with 53s. Blinds are 200/400 ante. You can raise here safely.
Resteal against stacks that are smaller than yours.