If you have acne blemishes, you might notice red marks when they heal. This is known as PIH, or Post-Inflammatory Hyperpigmentation. Treating the existing acne is essential, as well as wearing sunscreen to avoid dark marks from getting worse. A consistent exfoliating skincare routine can also help cellular turnover, which can help marks fade faster.

Your ethnicity makes you more prone to discoloration in the skin, given your skin tone. Be diligent about your skincare routine, and always make sure to wear SPF when you'll be exposed to the sun. If you are of African decent, be careful about using lightening products, as they may actually make discoloration worse.

If you aren't being gentle with your skin when shaving, the irritation caused by the blade can lead to marks and discoloration that takes weeks, even months to fade. Being gentle is critical, as is using a moisturizer after shaving to protect the skin. If you get blemishes as well, shave around the bumps, be sure to get on a routine to treat those first, before focusing on discoloration.