Sizes aren't standardized. An 8 from one designer may be a 7 or 8 from another (shoes made in Europe are usually narrower in front), so don't fixate on a number; always try on a half-size larger or smaller as well. To avoid buying shoes that are too tight, shop later in the day, when a bit of swelling is normal. And get remeasured yearly: Feet flatten and widen with age, pregnancy, and weight gain (if you slim down, your feet do, too).
Heavy shoes are suspect. They're just too much work to walk in: Your feet get tired and roll inward, leading to painful side effects.
Materials should be flexible. Patent leather is wildly popular this season, but tricky for shoes because it doesn't stretch to accommodate the foot (ditto for both plastic and fabric). Soft, high-quality leather or suede is ideal. Watch out for topstitching, which can reduce leather's elasticity.
Cushioning is key. Most feet are low in fat, so they need padding to be happy. Use thin gel inserts for greater comfort, particularly under the ball of the foot on high heels.
Mid-high heels make sense. Three inches is Hoorfar's limit. Not surprisingly, chunkier models are less inclined to wobble than the spindly kind (terrible for ankles). And your weight is better distributed if the shoe heel is centered under your heel, not placed too far back.
...And so do substantial soles. Ultrathin bottoms are torture, the doctor says: "There's nothing between your feet and the street." Luckily, some of today's hippest styles (wedges and platforms) have solid bottoms that act as shock absorbers. You can also ask your shoe repair guy to add rubber soles.
High-cut means lower risk. Shoes with sexy "toe cleavage" tend to rub against the foot at the widest point, where bunions form. A more covered toe casing is safer. Deep-dipping sides—or no sides—allow feet to slop over the edges instead of remaining properly aligned.
Adjustability is a plus. Look for laces, straps, or ties that can be loosened when the foot swells.