Dude, just tought it out. Yeah it sucks, and this is comming from someone who was had huuge problems with pre-gig nerves, but in the end nothing works better than just doing it. It will be scary for the first couple of times, but the more you do it the better it will feel and you'll get used to it.
+1.
I had a huge stage fright before I played my first gig with a band (and still have, actually). After the first two gigs it was like nothing. The first gig was so bad for me, I had trouble standing (I had to keep my knees "locked" so I wouldn't fall over, my legs were shaking that bad...) and that gig was with less than 20 people in the audience...
Week after that, I played my second gig with a band, the audience was 200-300 people AND they were celebrities for the most part and we were just an unknown band who were asked to play at a birthday party because our drummer and one half of the twins having the bd are workmates. Just so happens that the drummer's workmate is probably the most famous retired football player in the country... It wasn't as bad as the first gig, but I still had trouble staying upright... After that the other performances have been a lot easier.
Also, those two times we made a point of being completely sober, just so that we wouldn't fuck up because of alcohol. Of course we did some fuck ups, but we just smiled them off.
And after that, we made an agreement that if we ever fucked up on stage, we would just smile or laugh it off and carry on like nothing happened. Although it may sound silly, that really made it easier.
I was only playing rhythm guitar and doing backing vocals, but I think this applies anyway.
Yeah, for me is normal in my usual band where I play and sing backing vocals and the same old songs played during the last 12 years, but this time is different is a project similar to Spinal Tap, Bad News and that kind of stuff, stoopid lyrics and funny things. The success has been huge, radios, mags, tv, more than 100.000 downloads of the albums, almost 1.000.000 views in Youtube... I have to tell the jokes, sing, remember the lyrics and play guitar.
Another problem is that we have rehearsed only 3 days all together and is only 1 month to the debut.
Don't sweat it, you still have almost one month to practise.
And if the project is comedy style stuff, why not just make your antics look like its intentional?
http://www.youtube.com/watch?v=I8JiQCIzCZA#t=1m53s
Like some bluesman once said: If you make a mistake, let them believe it's just part of the song.