Safety is your first concern. The responsibility is all yours. Contemplate it, google it, write it out.
Next is legal. Talk with an insurance agent, and get the right supplemental insurance. Cover your ass. Uber only covers certain things and the rest is up to you.
Then - just get out and do it. Learn as you go, don't worry about the mistakes your going to make (we've all made them), and come back to this site with any specific questions you're going to have along the way.