Preheat oven to 375 degrees. Wash and peel your potato. Carefully cut the potato into very thin slices. Take a paper towel and rub some oil on your cookie sheet. Place the slices on the cookie sheet and sprinkle them with salt. Put them into the oven for 30 minutes. When they look golden brown and crispy, flip them over and sprinkle salt on the other side. Now put them back in the oven for another 20 minutes. When they're done, remove them from the cookie sheet right away, let cool and eat!