Predicament with a garter dance @ prom.. HELP, plz!

2moro is msms’s (MS school 4 math & science) prom & I’m going with my boyfriend who is a sr. there. They have the prom version of garter dances @ weddings & it’s pretty much inevitable tht I am going participate… :( but how can I do this with dignity & ensure that I do not dance with a horror of a partner? I’m feeling a super embarrassing moment coming on… (& I’m attending there next yr so its VITAL I make a good impression)