How can I have a cheap spa day at home?

Graduation is almost here, and as excited as I am, my skin and hair aren't. It was suggested to take a day off (which is no problem at all; we don't do anything on the last week of school) and have a spa day either with my friends, my sister, or by myself. I know the gist of the things I'll need (cubers, foot salts, candles, exfoliators, etc.) But where can I get all of the things I'll need without breaking the bank?