My wife and I got some plain cotton material in the favorite colors of the children. She made capes for each child. We ordered those narrow hairband sunglasses for masks (or girls hairbands if they wanted), diamond reflective snap bracelets, and plastic gem rings --all in assorted colors so we could match everything up (e.g., red cape, red snap bracelet, and red gem ring). We put everything in a solid, matching color loot bag.  When they came to the party, they were all issued their cape, power band, and power ring.