Shrinking a pair of too-big shoes means the difference between having blisters because your shoes are slipping and rubbing your skin raw, and not having them. Shoes that flop on your feet are not only uncomfortable but unattractive. When you know how to shrink your shoes then you can do this instead of having to make a second trip back to the store to return or exchange them.
Leather shoes
Fill the spray bottle with water.
Spray your leather shoes liberally but do not soak them all the way through.
Turn your hair dryer on a medium to high setting and then dry your shoes keeping the hair dryer at least 5 inches from your shoes.
Try your shoes on once the leather has dried completely. If they fit better you are done, if they are still loose then repeat the process as many times as necessary until they fit.
Canvas Tennis Shoes
Fill a clean spray bottle with water.
Spray your canvas tennis shoes until they are soaked through.
Put your wet tennis shoes into the dryer for 10 to 15 minutes.
Try your tennis shoes on. If they fit better then you are done, if not then repeat the process as often as necessary until they fit. It should not take more than two times to shrink them enough to fit properly.