Couple things from me with regards to this as well;
- I'd argue that you leave really old posts alone for the most part; it clogs activity feed, and it adds no real value, but again, personal discretion.
- Don't overdo the editting. Fizz brought up a lot of excellent points with regards to what you can change - ie. sprites, grammar, formatting, extranuous images etc. etc., but do remember that you aren't the user's grandmother. It's not a bad thing to be helpful, but ultimately, the responsibility is on the user, not you, to make sure the post is appropriate/easily understandable; ie. don't create a misunderstanding of responsibility by constantly & repeatedly overfixing a specific user's posts.
- If you can't understand it, chances are, other people can't. Tell a mod/editor and we'll help with it if it appears to be a load of unintelligable gibberish, but could still be a legitimate post. Pretty much, don't be afraid to ask for help, we're all potatoes here.
And a bit of an expansion, since on Fizz's first "don't" since he mentioned promotion rounds later too;
Sometimes users get annoyed over small things; you editting their question and removing/fixing certain parts, flagging the question, commenting something that's not completely positive, or if you become an editor/mod, for hiding and using admin powers. Just ignore it honestly; both Fizz and I have over 100 pages of wall posts, and a solid chunk of it is probably people complaining. You're doing a great job trust me!
That said, congratulations to Stellar, and any future experts/promotions.
Oblitigary comment, that my pet dropbear is far superior to Fizz's pet dropbear.