don't get too dressed up. but don't not get dressed up at all.the key to looking your best is feeling completely comfortable with what you are wearing and by letting your man know you like him enough to put in some effort with your outfit. depending on who the artist is I think for concerts opt for a nice pair of jeans and interesting top to dress it up a bit, or if its warm a skirt or dress with a good pair of shoes. not too much makeup, hair up I think is best. hope this helps!