You should not exfoliate for at least 2 weeks post-fraxel laser, and until all rough skin has finished sloughing off. When you do return to exfoliation, we always recommend chemical over physical (so something like an AHA, BHA, glycolic acid, lactic acid, salicylic acid, or retinol not a scrub or scrubbing device) and go gentler than usual the first time, as your skin may be more sensitive than usual.