Ingrown hairs are caused by shaving with a straight razor that shaves close to the skin leaving the end of the hair shaft with a sharped edge that tends to curl and grow back into the same hair follicle. Using an electric razor instead can help reduce and prevent these ingrown hairs by not cutting as close to the skin. Washing and exfoliating the skin before shaving can soften the hair making it easier to cut. Try cutting the hair in the direction it which it grows and not against it. Ladies would need to shave down the leg towards the foot instead of up towards the knee.