wear anything that fits your personality.
Jeans, a pair of stud earrings, wear your hair opposite of how you usually do (If straight/curl up/down) a flattering top that shows well on your body (Meaning the shape, not exposing to much skin) Maybe a necklace. And if you want to be fun, a birthday hat. Just because it's your day and your allowed to be silly.
Just some nice jeans with a blouse, or a plain black vest with a blazer or cardigan. Something a bit smarter than usual, but nothing too fancy. Maybe style your hair. Have a good birthday!
