Ummmm.... Depends, if it's a kickabout you don't know how many guys will come or what colour shirts they'll have so to be safe take a few different coloured shirts...
This was a joke, and it looks like it was on me. If anybody is interested I slept in and missed the kickabout, and layed in my bed instead looking at my girlfriend, who wasn't wearing any shirt. But thank you for the tip Jetlifari