* Glasses or thick-rimmed glasses, even if you don't need them
* A pocket protector
* A lab coat
* A plaid shirt
* A T-shirt with a science or math theme
* A computer-related accessory, such as a keyboard or mouse
* A book or other reading material
* A calculator or other math tool
Ultimately, the best way to decide what to wear on nerd day is to embrace your own personal style and have fun with it!