On our local news they had a segment awhile ago where one of the newscasters had her hairdresser on with some tips. Best I can remember:
1. Don't try to color your own hair if you're not used to doing it. Wear a hat, or a scarf. There is some kind of spray you can buy to touch up roots.
2. If you are going to cut your hair only cut 1/4 inch at a time.
3. If you are going to cut your bangs don't cut them straight across. I don't remember what she called the cut, but you kind of cut up.
4. For men, just a trim around the ears can make it look better.
I'm sure you can also find uTube vidoes on how to do it. Me? I'm going to let mine grow out a bit, lol.