Secondly, use your resources! For years I wrote out each student's name and glued it to their artwork. Now? I have the secretary print out names on sticker labels. SO much easier. She prints them one class per page, and if someone's work is missing I know immediately. One of those d'oh-why-didn't-I-start-this-years-ago things.
Thirdly, (is that a real word??) get the students excited. I have my students make invitations the week leading up to the art show. We just spend one class period making invitations. I print off the specifics like this:
so they can easily be cut apart and glued on the inside of the invitations. Students can make two or three and I've found they are more likely to come if they make a super-cute-and-covered-with-Mr.Sketch-smelly-markers invitation. This year, I'm also having students in third through sixth run little tables near their hallways demonstrating a technique or project we did this year. I'll try to remember to take some photos (next week!!!) and let you know how it goes.
Finally, remember that it's not the end of the world if everything doesn't go perfectly. I used to spend every night and weekend at school until the wee hours getting everything "just so" and you know what? It's only one night, so don't drive yourself to an early grave: get a good system working and do your best. It'll be great! (Even greater with a system that gives the students ownership AND allows you to keep your sanity!)