Just make sure YOU are gig ready and play the gig.
Practice the parts on your own , don't let yourself be the weak link.
Remind yourself that you never know what's gonna happen:
Don't call it a train wreck until after things crash and burn.
It's a party, not gig to live or die on.
Don't waste energy fussing about the rest of the band, time will prove who is up to the task of being in a band in the long run.
+1. While there is no "I" in "team," prepare all you can, so people won't say at the end of the night, "the bass player sucked."
Have fun!

