Ever put together an amazing cosplay, really nailed the details, and you’re about to leave for the con when it hits you: Where are you going to carry your phone, keys, death ray, etc? Doubly so when you realize you have no way to bring home all your loot!
When designing your cosplay for a con or other large event, it can be extremely useful to build storage areas into the finished product. Some costumes either have built in storage (off the rack pants) or can be adapted in the planning stages for a couple secret compartments for small items. Pockets take a little skill in my experience, so definitely check out tutorials if you want to avoid errors. I count myself lucky, as this is normally Jae's area of expertise.
Sometimes the easier option is just to build it on top of the cosplay. Whether a backpack that fits with the characters vibe, or some belt pouches for your superhero/Jedi/mage. Depending on the cosplay, they can be more accessible than a hidden pocket while carrying more stuff. I know one costume I wore had a pouch in the small of my back I couldn't reach unaided. I kept my business cards in it, as I knew there would be another person around when I needed it.
Finally, Handlers is the easiest of all. These underappreciated and amazing pack mules can carry your things, easily accessing bags full of snacks, essentials, and that cool new book you just bought. Of course, that includes finding a willing volunteer. In the past, I've asked friends of mine to play the role. They might be excited for the convention, but not so into cosplay, so it ends up being a win-win.
Regardless of the method you use, keep it in mind throughout the design and build process for your next cosplay! And if you're commissioning it instead (no judgment!) make sure to communicate with the builder about adding storage where possible!