Before using, you'll shave the area down so there isn't any hair above the skin's surface. You're better off using a fresh razor and a good shaving cream or gel to get a close shave rather than an electric razor. Otherwise, hair not cut close down will make the laser zaps hurt more than necessary.
When finished, rinse thoroughly and pat skin dry.Update. This is how the previous model worked. There are some similarities in how the newest system is used, there are also differences because it has five settings, a built-in skin sensor and digital display. (See Video: How to Use Tria Laser).