Clip on Earrings are made specifically for women with non-pierced ears. There are two types that are most popular:
1) Omega Back Clip on Earrings
2) Screw Back Earrings
The screw back earrings tend to pinch and are less secure. The omega back style clips on over a larger portion of the ear lobe and is more comfortable and secure. Speaking to a large number of women who have non-pierced ears (including my mom) most prefer the omega back style of clip ons. These are suitable for every day use.