Run it at a normal rate, which you will find later. Then dial it on the loudest song, then you are set. Basically give yourself enough headroom under 0 so you don't have to worry the whole show. You can still bump it up in post if it's too quiet, but if you clip, you are screwed. Keep that in mind! Set it on the loudest song while giving yourself some room before you'd hit 0, and enjoy the show.
If you move it around every song, it will be a bitch to fix afterwards.