Okay, get a good, solid idea of what music you want to play. Do you write music? If not, put together a list of songs that represents the music you like. Get your vision together in other words.
Then you've got to put the word out, which is relatively easy in this internet age. Look for players, make that a priority. When you find one, grab him. Do this all the time. You need to be out on the street, as it were, you need to keep your ear to the rail.
Do you have a place to play? VERY important. PA system? VERY important. (And don't forget the beer.)
You have to organize, you have to be the guy that makes it happen. There's a lot to think about. Otherwise you'll just be hanging around waiting for someone else to put something together. Might as well be you, right?