Know how the wrong size can hurt and how to fix it. Shoes that are too large can hurt just as much as shoes that are too small. Large shoes won't offer you enough support and cause your foot to move around too much, leading to chafing and scrunched toes. Shoes that are too small will leave your feet feeling cramped and aching at the end of the day. Fortunately, it is possible to stretch shoes out a little bit; it is also possible to fill shoes in to make them smaller.