Idea For a Costume Party At Work?

Need some ideas for a quick costume at work. Just started a new job and was told everyone will be dressing up for Halloween, on Friday. Not really enough time to do much or go out shopping..

Don't wanna be lame and not do anything, either.

I had this idea: I usually wear old (but comfortable) football jerseys and basketball shorts to sleep in. I was thinking about wearing my bright red KC Chiefs jersey - and some bright purple basketball shorts. My slippers and carry a blanket around with me. Then take a shower right before bed. And in the morning, just put the clean "man jammies" on and walk right into work with my hair all messed up. Looking like... well.... I just got out of bed.

Thoughts? Good idea?