How far you can customize your uniform depends on how strict your school dress-code is, so don’t go too overboard and risk detention!
Taking out your old laces for more colourful ones can brighten up the outfit and make it seem more fresh. Most teachers won’t notice if you bend the rules as to which socks to wear; patterns are fun and the lace collection from Topshop is very chic
Probably one of the easier ways to jazz a boring look is to change up your hair. Experiment with different styles or accessorise. Try anything from classic clips to neon scrunchies to beaded hairbands, whatever suits you.