I like the idea of putting the web address on the back of the shirt big enough so people can read it---on the front -some suggestions:
"this IS the color"
"true blue crew" our tailgate crew is using TRUE BLUE KREWE
"WHY BLUE?" then underneath it in smaller letters--''see back"
"I GOT BLUE" sorry Todd
"blue is the color of my true love's--- university" ah corny
"HERE'S YOUR BLUE"