1) Definitely - most def - no contact! This means not even driving by his house or looking at pictures of you two. Do not call him until you do not feel a desire to talk to him. At that point, maybe you can be friends.
2) Do all the things you like that he didn't - for instance, my ex didn't like dressing up to go out, so we often ended up at dives, but now I am enjoying my favorite martini/wine bars again (with the occasional dive, because I like them - in moderation). Revel in your ability to do so.
3) Lead a healthy lifestyle - eat right and exercise. It will keep your energy level high and release endorphins.
4) Treat yourself and look f-ing hot whenever you go out. Shallow, but the male attention and your newfound opportunity to bathe in it will be refreshing and boost your confidence.
5) Spend lots and lots of time with your friends... they have always been there for you and will do so now.
6) Join clubs, volunteer and meet new people. It will remind you how fun and interesting you are. You are so much more than his girlfriend.
7) Try not to overanalyze (I know it's hard for us girls). You can't explain what happened and you can't change the past, you just have to accept it.
8) Don't get mad at yourself if you have setbacks and don't be afraid to be a little sad... it takes time.
I'm doing all these things right now and LOVING every minute lately. It took awhile, but it gets better! Good luck!
