Bra straps showing under spaghetti strap vests.
Visible pants
Sportswear (espescially with 'designer' labels) & trainers when not actually doing sport.
Ballet pumps - esp when too big so you can see the person 'holding' the shoe on by bunching up their toes. Real ballet shoes have elastic or ribbons to hold them on.
Anoraks - I will never be old enough for one.
Massive earrings that drag the lobes out of shape.
Anything with the manufacturer's name plastered across the front - why be a walking advert.
Boots with peep toes - boots are for cold, wet weather so cutting a hole in the front is pointless.
Gerbil norks / back boobs / boobs worn round the waist due to lack of decent bra - the bigger they are the more expensive the scaffolding needs to be. Was fascinated / appalled by Strictly's failure to hitch Anne Widdecombe's boobs away from her waist.
But I do like waterfall cardigans - though you do need a decent bra underneath.
Kids in 'tart message' t-shirts - DD1's friend had one saying 'I want to be a WAG when I grow up' - scarey