You will need a double layered tumbler. All new Starbucks iced tumblers have an inner core.
Next grab some glitter from your local craft store. Im partial to the Martha Stewart collection. She has lots of different colors and forms of glitter.
You will also need adhesive spray. Any brand is fine and you can most likely find it in the glue aisle at any craft store.
Unscrew the outer core of the tumbler. This is the piece that will be sprayed. The inner core stays separate.
Quickly spray at least two times in the inside of the outer core. Make sure you are able to cover the entire space.
Next (you will need to move quickly) power as much glitter as you see fit into the cup. Cover the top and shake. This process will be fast so don't waste anytime!
Replace the inner core after a few minutes and wait over night for the everything to dry. And there you have it! One glitter tumbler :) now..where is the coffee?