The first step to becoming a successful shoe-shopper is knowing your way around the shoe. I'm talking about "shoe anatomy". Various brands and department stores may advertise "premium leather uppers" and "light-weight midsoles", but if you don't know what an upper or a midsole is in the first place, it can be tricky to know if you are getting the right pair of shoes for your feet.
Think of a shoe as divided into 4 major parts. First you have the 3 soles: the outer sole, the insole and the midsole. The outer sole, as you can probably imagine, is the part of shoe that make contact with the ground. The part we normally just call "the sole". Outer soles can vary in traction and shock absorption. Some people prefer thin outer soles that maximize their foot's contact with the ground; others require a thick sole that will cushion their feet and legs. The heel is generally associated with the outer sole, and it is located at the back of the foot. Heels vary widely in elevation and adjusting heel height can go a long way to dealing with foot pain. Generally speaking, the higher the heel the more pressure on the front of the foot.
The insole is the part of the shoe you see when you look inside your shoes. It is often removable and is associated with arch support. It is common for people who need extra support to insert customized insoles in place of the ones provided by the shoe manufacturer.
The midsole is the part of the shoe sandwiched between the insole and the outer sole. Midsoles vary in material, weight, thickness and flexibility. A rigid, heavier midsole is good for feet that require extra support. A flexible, lightweight midsole is good for active people who want to maximize their mobility.
The fourth major part of the shoe is called the upper. This is the part that covers your foot. It can be made out of canvas, plastic, leather and other materials that vary in breathability.
When examining the upper part of the shoe, it is important to pay special attention to the toe box and the vamp. The toe box is the part of the shoe that encloses your toes. It can be square, pointy or round. Whatever the shape of the toe box, it is important that it provides your toes with enough space to spread out naturally. The vamp is the part of the upper where the laces or Velcro is usually placed.