Wrinkles may form on the bottom of the pool liner in above ground pools. A pool liner can stretch or lose its original placement over time, which causes it to wrinkle. Not only do wrinkles look bad, but they can also cause minor injuries to the feet, most notably stubbed toes and torn toenails. You can usually fix a wrinkled pool liner yourself, without the need for professional help.
Drain the pool water until only 1 inch of water remains on the bottom of the pool.
Climb into the pool and get on your hands and knees. Choose a wrinkle and press it toward the wall of the pool with your hands. It's best to start in the center of the pool and work your way out, until all the wrinkles are pushed against the wall of the pool.
Remove a portion of the railing on top of the pool wall. The process for this will differ depending on your pool, but it often requires you to remove screws and pry the railing away from the pool wall. Call the pool manufacturer if you have any questions.
Pull up on the pool liner until it looks smooth and taut below that particular section of the pool railing. Put the railing back in place.
Move around the pool and remove the railing one section, pulling the liner below each section taut as you go, until you've made your way completely around the pool.
Remove the wrinkles on a warm, sunny day. The liner may be easier to manipulate when it's warm.