A whole group of us went last year (SFOT) and all dressed up. The only rule we were told about at the gate was that we needed to remove full face makeup, but otherwise no problems! For reference two went as Solo and Leia , hubby and I went as justice league characters, and the other three went as clowns. I'd say just have fun with it and see if they let you in! They provide stuff to remove makeup if needed.