....minimise a big bust

First of all, let go of the embarrassment. This is a wasted emotion and won’t make your bosom any smaller or your dress sense any better. Be rational and calculating when buying clothes and getting dressed. The goal here is to divert the eye downward to balance the bust with the rest of your body. Wear slender pants and skirts for a slim silhouette and choose tops that are a little bit loose but not oversized. And, without exposing your cleavage, aim to flash a bit of skin around the décolletage area to open up the area around your face and neck. Cross over or wrap tops are good for achieving this look. If in doubt stick with dark colours and avoid belts as they will cut you in half and keep the focus up top. But most importantly, get fitted for the best quality bra you can afford.