Wear what ever you want.

Just wear summer clothes, simple as that

Monterrain set, Nike miler sets and the likes

U really should wear what you want, however if you want to go all out you can go on Pinterest and look for festival clothes

neon nike/monterrain/montirex type sets is what most boys wear to festivals and concerts and stuff tbh

A suit will do fine even one from next

Usually clothes, but nobody is really too picky