Well ingrown hair are the same in all places in the body ,i mean same causes and mechanism if you were a man or a woman any place of hair can suffer from ingrown hair(hair under skin )
however this is a more detailed ways and tips you can use to prevent hair on the legs :
Treat an ingrown hair with products that contain salicylic acid, azulene and/or witch hazel, which will help reduce the redness and swelling. These products also can exfoliate, moisturize and clear clogged pores. Treat freshly shaven areas with these same topical ointments to help prevent ingrown hairs from forming.
Coax the ingrown hair out with a tweezer. Ingrown hairs lie just under the first layer of skin and can be lifted out by gently scraping the skin surface. Carefully lift the ingrown hair, but do not tweeze it. Poking at ingrown hairs will irritate them. Treat the area with an ointment, such as those mentioned in Step 1.
Exfoliate the area every time you wash. Use exfoliating mittens and scrubs that contain gentle exfoliates and salicylic acid. Body scrubs are great for exfoliating, but use the products before shaving and not afterward.
Adjust your shaving technique for areas prone to ingrown hairs. Avoid foam-based shaving creams, and opt for non-acnegenic creams when shaving areas prone to razor burn. Avoid a very close shave by shaving with the hair growth, instead of against it, and do not pull the skin taut or press too firmly on the razor. Too close a shave will create an opportunity for hair to grow back into the skin. When taking a shower, shave last to allow the hair to soften before you shave it. Use a soft-bristle face brush on your legs to lift hair off the skin surface and gently exfoliate the skin before shaving.
Avoid ingrown hair triggers. If you are prone to ingrown hairs on your legs, avoid the things that trigger their growth. Waxing is one of the worst things you can do to sensitive skin. Waxing pulls the hair out at its root, which causes hairs to root more deeply under the skin surface, giving them more time to infect and causing them to become ingrown even deeper in the hair follicle. Do not tweeze or wax areas of your legs that are prone to ingrown hairs.
Prevent ingrown hairs in the summer and when exercising. Ingrown hairs on the legs can be caused by irritation from working out, sweating and thighs rubbing together. In the summer or during a workout, use petroleum jelly, talcum powder or deodorant on the insides and backs of thighs to prevent the irritation caused when your thighs rub together. Wash these products off immediately after a workout or long walk so the hair follicles can breathe again