You're not listening. Don't 'do your best' not to touch wheels. GUARD YOUR FRONT WHEEL. Don't touch wheels and if you're not a complete friggin idiot, you should be able to manage this. Here's one tip: if you start getting too close, TEMPORARILY float your wheel over a few inches to the RIGHT, that way if the guy in front of you slows down you might over lap wheels, but you won't ride right up his rear wheel. Don't ride like that for too long, only if you get too close and you can't back off immediately. But until you're comfortable, try to give yourself enough space to be safe and relaxed. As you gain more experience you will get more comfortable drafting at tighter distances.

'I'll do my best'. You guys kill me. Look, I'm less worried about you than the guys behind you who may also crash into your silly ass. Please keep this concept foremost in your mind at first, it will eventually become second nature. I still focus on that thought when the pace line or pack gets fast and road surface conditions get dicey, and sometimes they do.