I know we're not supposed to mention them on here but Trinny and Susannah's Body Shape Bible honestly has been a stylesaver for me. First thing is to make sure you actually are an hourglass, and the number of posters claiming to be an hourglass / pear, or an hourglass with skinny legs, suggests there is some variation in what people think it is. But if you've checked and you are (big boobs, smaller and relatively high waist, big hips, chunky upper arms and thighs, quite small hands and feet), then their tips are brilliant. I've saved a fortune on mistake buys and gained confidence by:
defaulting to bootcut trousers (balance out the bum) and scoop or V-neck jumpers / cardigans (neat, slim fit)
nothing flouncy or ruffly, we're feminine enough with all the boobage and anything frilly looks like a 70s horror show. Similarly, bulky material, thick scarves, heavy jumpers, all drown us and we just look like a shapeless blog.
fitted knee-length dresses with a nice stretch fabric, plus boots to balance the heavy calves, plus fitted jacket for smartness (my work uniform)
in summer, cropped trousers and cute shoes, plus fitted blouses rather than t-shirts
Principal boy silhouette works well - fitted tunic to top of legs, plus thick leggings and boots (do not be tempted by trainers)
small prints (big ones swamp our smallish frame)
avoid high round necks and closed collars (look like boobs solid to the waist), batwings (look like boobs trying to escape sideways) and, I'm afraid, thick feature belts, which chop a short body in half and make us look shorter and wider still (the hourglasses that suit belts are actually vases).
Curvy shoes good, pointy shoes bad.
10% smarter than everyone else to look the same (ie we look 10% less smart than everyone else as we are borderline frumpy in shape)