What to wear for my bands next gig?

I'm singing some metal songs at a party with my band in afew days. we've already gotten the songs down pat, so i wanna think abut wardrobe. im 5'8 shaggy brown hair, blue eyes, caucasian, in shape build and we're playin clic metal (Ozzy, Dio, Metallica, etc). Our band is called Radioactive Rebound. any suggestions i can follow on a 20 dollar budget or using clothes i already hav are welcomed, THANK YOU!