Razor bumps are small red bumps that appear after shaving. Shaving pulls moisture from the skin, which can produce irritation, resulting in itchy skin and the unsightly red bumps. The red bumps actually are ingrown hairs. Once the bumps have developed, only time can completely eliminate them. Prevent razor bumps from occurring in the first place by using the right products and proper shaving technique.

Shower and Exfoliate

Shower or soak in a tub of warm water for at least 15 minutes before shaving. This will open the pores and soften the hair, making it less likely the skin will be irritated during shaving. Exfoliate the area to be shaved with a mild scrub the day before shaving, or gently rub the area with a washcloth during your shower or bath. This will remove excess skin cells that can block the pores and make ingrown hairs more likely.

Shaving Cream

Use a shaving cream that is specifically formulated for sensitive skin. Ingredients such as vitamin E and aatmeal are common in moisturizing shave gels. Apply shaving cream upward, against the grain of the hair. This will help the cream penetrate the hair follicles.

Shave Properly

Shaving against the direction of hair growth might cut the hair closer, but it is also more likely to result in razor bumps. Instead, shave the direction the hair grows. Although this will not result in as close a shave, it will put a blunter edge on the tip of the hair, making it less likely to grow back into the skin, causing razor bumps. Change your blades regularly, as a dull blade can exacerbate ingrown hairs.

Moisturize

After shaving, rinse the skin with warm water and pat it dry--don't rub. Apply a moisturizing cream directly to the freshly shaved area within three minutes of shaving. For extra protection, use a cream that contains hydrocortisone.

Source:

Skin Biology: Preventing razor bumps

Go Ask Alice: Tips for preventing ingrown hairs