If you're lucky enough to live in a place where these are already trending (or has already trended and gone) and you have a lot of plain ones laying around that you'd be willing to sacrifice, go for it! Not like you'd really be sacrificing anything because this DIY will make your bralet look fabulous and really be a statement piece!
If you're really wanting to invest a lot of time with this, I'd suggest embroidering beads and such on to your bralet (if it's thin enough b/c if it's too thick your hands/fingers will hate you in less than 30 minutes).
If you're looking for a quick little statement piece to wear out later tonight or within a few days and you don't have a lot of time on your hands I suggest hot glue or e6000 glue (my all time favorite). just be careful with the dreaded overgluing that could happen. be really careful.
Grab some things like sequins or jewels or pearls (as seen below) or even some unconventional things like bolts and safety pins *drool* for that all out upcycled look.
Let your imagination run wild!
Good luck! <3
Courtesy of outsapop
ps i'm adding this to my list of spring/summer DIYs :)