I completely second that, Doc...
JUST DO IT.
Just, don't expect to be successful. Don't expect to make ANY money. Don't expect it to improve your social life with the ladies. Don't expect it to ALWAYS be fun. Don't expect your first band to last. Don't expect that anyone else will like your music. Don't expect to get signed....
Now, those things MIGHT happen. But probably not. But in the meantime, you will discover the joy of playing WITH OTHERS (we often forget that, as arranger OMB's, here), and there is little else on earth that feels so good once you get it right. Just don't expect THAT to come real soon. It WILL come, eventually, but don't let unrealistic expectations cause you to give up.
It's a calling, not a job