The next step is to purchase a good pair or running shoes that provide the cushion and support necessary for the 800 to 1000 foot strikes per mile that you will be utilizing. This is your most important piece of equipment and will go a long way toward keeping you injury free. You may want to go shopping with a running friend or visit a store with knowledgeable salespeople who will measure your foot right up front. Be certain to take a pair of socks that you will be running in to ensure a good fit. Try on several pairs of different brand shoes and jog around the store to see how they feel during the running motion.
Fit is crucial.
There also should be very little slippage up and down in the heel counter area. Depending on the brand, running shoes have a tendency to run a half or full size smaller than street shoes. When you get them home, it's a good idea to walk around in them for a day or so before running. Your body mechanics will dictate, to a great extent, your stride and form. There are, however, some general guidelines to follow.