Summarize this article:

If ingrown hairs become chronic and you try to use some object to dig out the ingrown hair, scars can form. Avoid any “bathroom surgery” and don't use tweezers, needles, pins, or anything else to dig out an ingrown hair.  This will increase the risk of a scar forming and can increase the risk of spreading the infection. You need to hold off will all hair removal in the area until the infection is cleared. Ingrown hairs appear to form when the hair is cut at or below the level of the skin, leaving a sharp edge to the hair which then grows sideways into the skin. Continuing to remove hair from the area could result in additional ingrown hairs or further irritation to the infected area, both of which you want to avoid. Make sure you are not over-drying your skin. Use a bit of moisturizer on the infected hair after every treatment. This can help soften the skin and can reduce the risk of skin damage and scarring.

Summary:
Never try to cut out an ingrown hair. Stop shaving, tweezing, waxing, or removing the hair in the affected area. Keep the skin moisturized.