Home Hair-Beauty Mix baking soda with coconut oil and scrub under your arms, baking soda gently exfoliates the skin removing any dark or rough patches making it softer and smoother. 1 tsp of baking soda with a tsp of coconut oil; scrub for a few mins very gently; leave it on for 5 10 mins and wash off. Do as often as you like, exfoliation is an important step in your skin care routine.