Stick on bifocals can be an inexpensive way to turn your single vision glasses into bifocals. Wash your hands, glasses and stick on bifocals with soap that DOES not contain lotions or oils. Use clean warm water to apply the stick on bifocals.Try on the glasses to make sure the bifocals are in the correct spot, the vision might be a little blurry until the stick on bifocals have dried. It is best to leave them to dry overnight! These stick on bifocals can be reused and can be trimmed to custom fit your glasses.Hope this helpful.