When we go to events and wear our Star Wars costumes, like my X-Wing suit, we carry our gear in bins and change when we get to the site. I got tired of searching through my box for all of my X-Wing parts so I decided to build an equipment rack for the underside of my trooping box lid. It holds my chest box, wrist compad, and data cylinders up and out of the way of my boots, blaster, flak vest, and flight suit.
For Star Wars good guys the gold standard of costuming is the Rebel Legion. My Rebel Legion profile is here. They have lists of what you need for any Star Wars good guy costume and their message boards will point you to the vendors. If you want to be a Star Wars bad guy you'll find the same information at the 501st Legion.