Costumes are mandatory, and can be both elaborate and incredibly simple.
You are your own character in a dive bar in a galaxy far, far away.
That could mean aliens or creatures of all species and sorts - smugglers, pilots, gangsters, bounty hunters, criminals, etc.
Think vests, khaki jackets, ponchos, capes, straps, goggles, etc. A lot of looks you'd see in a Western would work. Wasteland gear works. Playa gear is perfect, and so on. A dash of face paint, an alien hair style. Earth-toned desert garb is simple, and a little goes a long way...
Please avoid things that would look out of place in this setting, such as ball caps, printed text, logos, plaid, etc.
