When you pull out a hair whether with waxing or tweezing the hair takes 10 days for it to grow back. Unlike when you are waxing we do not need the hair to be longer (they need it to be longer so there us something for the wax to adhere to). With laser we need the hair to be short so the laser will pick up the hair at the skin level and penetrate down into the follicle.
If you are currently waxing we just need the hair to be coming back in so schedule your laser treatment for 10 days after you have waxed. The hair does need to be short so if it is a little long run over the area with a razor the day before. If you have waxed more then 10 days ago that's fine- you just need to shave the day before so the hair is short but the area isn't irritated.
If you have in growns and irritations from waxing then exfoliate the area with a loofah sponge every time that yo shower before coming in for your appointment, while the hairs are falling out after the laser treatment and even after the hairs shed. The exfoliation will help to get rid of that scabbing and irritation. Even after one round of laser the bumps and in growns will get significantly