You should not shave two hours before a spray tan, as this may cause skin irritations or issues related to the spray tan developing unevenly. Shaving can also disrupt the natural oils on the skin, which may interfere with how the tan develops. If you must shave, it is better to do so at least 12 hours before your spray tanning session to minimize any potential problems. Also, exfoliated skin can make it more difficult for a spray tan to adhere, so avoiding any exfoliation before you visit the tanning salon is best.