Influence the set list so your first few songs are confidence-builders. They are the ones that please the audience but are also ones you feel really comfortable with, as a group. This will get the gig(s) off on the right foot, and energize the rest of your set.
Also, record the last practice's beginnings and endings, and then distribute them to the group so they can listen to them on their own.
Simplify them, where possible. In jazz, we have two or three standard types of beginnings and endings we use, and have hand signals for them. Also, watch on stage for people who need help, and give it to them. I walk over to struggling people and talk to them if they have a hard time. Once, I was in that boat, and walked over to a guitarist for help and he ignored me. Totally un-teamwork like. And don't be afraid to be explicit about song structure issues before you start a song, even if it seems redundant. You never know who might need it. Also, say the name of each song before you play it. A few times, people have skipped a line on the set list and started playing the wrong song -- usually this happens when the band is struggling with other issues, like lack of confidence, insufficient rehearsal, or equipment problems. If someone missed a line on the set list, and plays the wrong song, and that happens early in the set list, it can be a real confidence killer - in fact, anywhere in the set list, it can be a confidence killer.
Make sure one person is the leader of structure, so everyone knows who to watch for structure cues...
Good luck. Ultimately, you have to stand up there and abandon yourself to the results of the rehearsing you did. And the proof will be in the audience reaction and whether you get asked back....let us know how it goes!