Shoes that are too tight create friction, which eventually causes irritation on your skin. Therefore, getting sandals that fit properly is the first step (literally) toward ensuring you don't get blisters. You can also prevent blisters by keeping your feet dry, wearing socks, or applying a lubricant like petroleum jelly to troublesome areas. Fortunately, after you recover from blisters, your feet may naturally adjust to the added friction of a new pair of sandals.