Depilatory Magic. The shaving powder recommended by the national Medical Association as an effective shaving method for the relief of razor bumps in black men. HOW TO USE Before using Magic Shaving Powder for the first time, the following test must be performed. Wait at least 36 hours after using a razor or depilatory product before doing this test. Mix a half teaspoon of Magic Shaving Powder with equal amount of cool water. Apply to one inch section of beard area. Leave on for no longer than five minutes. Moisten if necessary. Rinse away thoroughly.