What do you do when you get the sunglasses on Super Mario sunshine?

Answer 1

To get the sunglasses, you have to clean off the shine gate and get the shine Sprite that appears, which usually takes about 20 or 25 shine sprites. You can only wear the sunglasses in Delfino Plaza though. If you want to remove the sunglasses, simply talk to the merchant again, and he will remove them for you.

P. S. If you acquire every single shine sprite, you can get a tropical shirt to go along with your sunglasses.