Adapt your dress to the type of concert you are attending. You don’t want to sport a cowboy hat to a punk rock show. This should be obvious, but if you don’t know much about the band your friend is dragging you to see, do some research.
Wear the right band's T-shirt. Do not wear the T-shirt of the band you are going to see. You already like the band or you wouldn’t be there, right? So pick T-shirt for another band to show off your musical taste or interest in the genre. Band tees are the most popular outfit for many shows, and wearing the right band T-shirt can earn you spades of indie cred.
Go farming. For country, alt country and even some indie shows, it’s common to see guys sporting a hip cowboy-inspired dress shirt. Stripes, plaid and picnic table gingham are three ways you can’t go wrong.
Dress vintage. When in doubt, a cute vintage shirt and stylish jeans will work for any concert and for both guys and gals.
Wear sensible shoes. The pit is no place for pumps. Guys and gals alike should be weary of sporting a pair of sandals in the mosh pit. A pair of cute-yet-comfortable sneakers is the best way to go for almost any concert. Remember, if you’re standing in the pit for hours (where, no doubt, someone in the crowd will spill beer on your feet!) you want something comfortable.
Leave the purse or man-bag at home. Unless it’s a show with assigned seating, don’t lug a bag into the show. Nobody likes to be trounced in the pit by an oversized clutch. There are only so many items you need at the show (cell, ID, cash), and most of these can fit in your pockets.
Be yourself. Rules or no rules, concerts are often the place to get away with that jacket or cuff that you just can’t pull off at the supermarket.