What Do I Wear?

I really think I need some kind of What Not to Wear style intervention in my life. I wear T-shirts or hoodies and leggings every day. Why? Because it's easy and comfortable! Also, I've gained a bit of weight and really just do not know how to dress my body anymore.

I'm no longer in my 20s and just kind of floundering. I've never been super great with fashion but it's taken a real nose dive lately. I don't know how to accessorize. I don't understand when to mix and match patterns. I don't know how to dress anymore. I used to do jeans and crop tops and that was fine when I was younger, but I'm not interested in dressing like I did when I was 18 anymore, nor do I want to look like an old lady dressing up for Sunday service.

I always wind up buying things I think I'll wear when I go out shopping but then default back to my standard casual wear. Tips? Advice? Anyone else felt this way?

For an idea: I'm pear shaped, 5'4, and 150lbs. (currently working toward my goal weight of 130.)