I had a brief look at the Toast website the other day when there was a thread about it. I'll have another look around.
I am 30, about 5"5 and a size 12. DD is almost 9 months and I'm still breastfeeding so my boobs are much bigger than pre-pregnancy. I am no lady of leisure, but can't say I do much in the way of gardening.
You need to ease yourself in to dressing like a grown-up.
Start small by swapping the trainers for black and white Converse or nice flats like these.
There's nothing wrong with jeans but go for slim fitting darker denim if you want to look smarter. Leggings under tunics or short dresses work well.
Toast, White Company, Zara and H&M are all good for tops. Make sure you get fitted shirts. If you are larger or nork go for ones that come in under the bust - far more flattering. Belts can work well too. Oh, and get a decent bra. makes a huge difference.
Bags - spend a reasonable amount on one decent leather bag that goes with everything. Brown or black is your best bet.
I live in jeans, t-shirt tops etc too, but once you shop quite carefully for these things (as opposed to slinging on the old gap/primark shapeless stuff you've been getting by on for years), it can suddenly make a big difference. Whistles great for jersey t-shirty tops and tunics that go well over jeans. Topshop good for jeans, also koodos.com great for discounted sevenforallmankind jeans (fit brilliantly, very flattering). Cos doing lovely jackets, coats, etc at the moment, plus quirky jersey tops. All Saints good for drapey assymetric knitwear, though not everyone's style. Also, sweater dresses over leggings with boots good for the winter. Can hide a multitude of midriff sins.
Try browsing web sites - it's easier to look at brands on websites, and to buy whole outfits in one shop/brand, than to look at magazines that have put complicated looks together, if you aren't used to shopping.
I have just bought the roxanne skinny(ish) jeans from there for £40... I tried on a load in somewhere like john lewis first, as I had no idea what size i was. koodos having a giant sale just now so are low on decent stock, but they are worth checking fairly regularly. Also, Joseph Essentials are having a big sale just now, including all their seven jeans, but they will be more £££ than koodos (but will have much better selection). where are you wem? Lots of people swear by paige jeans too but i've never tried them to be able to advise....
(tk maxx has superfine jeans in a few weeks ago but i didn't like the fit or feel....)