If you want a choose right running shoe in your foot so really these factor are useful for you:-
1. SIZE- In the running shoe not purchase a perfect grip shoe. The reason of you run more that your foot get expanded naturally. So rule number one is to leave a thumb's width of space between your toe and the end of shoe to avoid any size issue at a later stage.
4. Rule number four check your foot is pronated, under-pronated and over pronated.If you are pronated so you come choose any kind of running shoe that are comfort and lightweight.