Ask the most experienced GM from the group to support you.
When I ran my first game I had the groups founding GM backing me up. That really helped me find my feet. Not to mention I had a guide to some of the parts of the GM role that I was unfamiliar with.
A word of caution with pre-made adventure paths – read them through beforehand. I took part in one game where the GM had as little idea what was coming next as we did. Our party pretty much derailed the entire game before the end of the first chapter. I won’t go into details but it was not a great game. It was not bad but it lacked a certain something. Things got better from that bad start but take it from me – know the game before you start.