I feel like I’m finally getting somewhere with this (it’s taken 5 years) so here is my advice.
Find bottoms (I like stretchy jeans, skinny jeans), smart tops (I like shirts or t shirts) shoes (I like trainers) and jacket (I like leather jackets).
For each of these items individually find a style that is comfy and flattering (just give up on things that aren’t comfortable, you have a baby and you won’t wear them even if you buy them… trust me).
Choose styles that can cope with stains and lots of bending down and playing on the floor e.g. probably not white, not suede, not silk etc.
Find the companies that do them in good quality, long lasting materials and are expensive. Try them on in the shops (this is so painful I know but you only have to do it once).
Buy them for half price or less on eBay.
Buy at least 5 tops, 2 bottoms, one shoes and 2 jackets. Wear on repeat.
Take care of them - deal with stains, clean your shoes, dry them on a hanger etc.
Buy some new good quality leggings and jumpers because you WILL still want to wear leggings and hoodies so have ones without holes and stains.
Get a hair cut.
Get fitted and buy a new bra.
Good luck!