They should consult with a physician before undergoing any hair removal method that uses energy or involves chemicals or drugs. Bikini area is a common question I get. Shaving is most popular, though it's important to moisturize heavily before and after, and use a new blade. Many find a product called Tend Skin to be helpful in reducing irritation and razor bumps. Waxing can be painful, but it lasts a while.
Electrolysis is very painful for most, but if done properly, it can be permanent.
Some with light skin and dark hair have found laser to be a good option, but it's extremely important to avoid sun before and after laser treatment to avoid discoloration that can last many months. Legs are still shaved most frequently, with waxing and cream depilatories being the second and third most popular options. Some women with light skin and dark hair have found laser to be a good option, but there's limited data on long- term effectiveness and success rates. Some women ask about arm hair. I generally don't recommend shaving, since the hair feels coarse and bristly as it grows out.