Here is a quote from a guide on Ebay, written by "itradeforyou", who has her own website:
"I know many parents, grandparents & relatives are spending big $$$ on American Girl Dolls for their favorite American Girls. Here are some tips on how to keep the dolls looking good for many years of wholesome playtime fun. First, you need to make sure to purchase a set of proper hair care supplies before ever handling the doll's hair. At a minimum, the set should include the following:
· wig brush
· misting bottle
· doll-friendly rubber bands
The brush should be used ONLY on doll hair. Using a human hair brushwill damage the synthetic fiber of doll hair and can also make the hair dirt-prone. Also, you must lightly mist the hair with fresh water before brushing or styling. This protects the hair and makes it much easier to comb through. You should always start at the longest part of the hair and remove any tangles before working your way up to the base of her wig. This prevents excessive pulling and breakage. Non-snag rubber ties are also a must-have when styling the hair into ponytails, braids or up-do's. They will not snag or cause tangles and come in various colors to match the doll's hair color. You can find a good selection of brushes and other supplies at your local Sally beauty supply store. Their prices are reasonable and they have a frequent shopper program that offers nice discounts."
From "Justmagicdolls.com" "Start at the ends of the hair and brush the tangles out of the bottom 2" or so. Work your way up the section until you can draw the brush down the hair without resistance. Brush carefully, holding the top of the hair with one hand. Holding the head keeps hair from being pulled out and also protects the neck from becoming loosened. Brush gently so you do not pull out much hair -- pretend you are brushing a real girl's hair ("Sorry, Felicity, didn't mean to pull.") After you finish one section, pin it up and take out the next. Work your way around, section by section. "
"Start at the ends of the hair and brush the tangles out of the bottom 2" or so. Work your way up the section until you can draw the brush down the hair without resistance. Brush carefully, holding the top of the hair with one hand. Holding the head keeps hair from being pulled out and also protects the neck from becoming loosened. Brush gently so you do not pull out much hair -- pretend you are brushing a real girl's hair ("Sorry, Felicity, didn't mean to pull.") After you finish one section, pin it up and take out the next. Work your way around, section by section. "
I will summarize some of what I have learned from some of my favorite doll hair care sites and articles:
1- Only use a wig brush. Using a human hairbrush can ruin the synthetic fibers and the oils from human hair and scalp will attract dirt and make the hair grimy.
2- Here is one quote:
The only other things you need are a misting bottle and some hair clips. Optionally, you may want some spray detangler. Some people swear by Son of a Gun as a detangler/conditioner; yes, the car vinyl protector from STP. You can buy this inexpensively from department stores (like Target). Other's use people spray detangler or a mixture of fabric softener and water. For hair that is really tangled, you might also want to invest in a metal tined comb like the one on the right below. You can find these in the dog grooming section of a pet store. A metal hair pick is better for curly or highly textured hair, but see the note above about treating the curls gently. You can get a tiny one from American Girl or buy a people-sized one at Sally's. (Personally, I really like the Sally brushes!) (Do not use any other type of brush or comb, as it will ruin the hair.)
3- Divide hair into smaller sections, mist with a little water and maybe a little detangler, and begin gently combing starting at the bottom of the hair. (One website states that the folks at American Doll Place state that misting the hair and using the wig brush are the two key important ingredients to keep the dolls hair nice.)
4- Continue gently brushing small sections from the bottom up, misting top and bottom and underside of the hair, brushing up slowly until you can gently brush from top to bottom without snagging. Hold top of head gently to steady the doll as you do this. You may need to pin each section of hair as you finish to keep it out of the way.
5- Sometimes as I have gone thru this process with dolls that have really tangled and messed hair I have squirted a bit of my little girls hair detangler on it. One sight advocates putting a TINY amount of baby oil on your palms, rub hands together then massage into hair. I have done this, but I would not do it too often as dolls hair can get build up and also the oil can attract dirt and dust. The above-mentioned “Son of a Gun” is advocated on many sites, I have not used it however.
6- Velcro on dolls clothes can wreak havoc with doll hair! Keeping the dolls hair in braids or other styles may help preserve her hair.
7- Frequent care as outlined above should keep it in good condition. Sometimes hair can get dirty from build-up or can get frizzy or dry. A lot of playing with the hair can, over time, frizzy it up I have read. I have been restoring several dolls… I like to collect and restore the Ideal Crissy dolls from the 1960s and 1970s (Yep I just “dated” myself!) and the American Girl doll hairs. In my research doll restoration/repair sites have advocated the following treatment, and seems to be a popular treatment in general for fixing dry/frizzy hair. I can tell you it has worked for me and I absolutely love the nice results!
1- You can wash the dolls hair with several things: You can go to Sally’s and purchase some wig shampoo, or purchase some doll wig shampoo like “Twin Pines” over the internet (I like their products!), or do like I do… I use a very gentle baby shampoo. Before shampooing be sure to protect the doll by completely covering her with a plastic bag. Also, get a towel or something to protect your dolls eyes. Or cover eyes with cotton, or tape. Water in her eyes will rust the sleep mechanism.
2- Washing the hair: Use COOL water!!!!!! Warm to hot water can loosen wig cap and also loosen curls. While we are on the subject of heat the girl at the beauty shop told me that you cannot use heat in general with synthetic hair. So, no hot water, no curling irons, and etc.
3- Careful not to get the wig cap to wet in general. You can loosen the wig cap.
4- You can add the shampoo to a sink full of cool water, swish, then put the dolls hair in there and wash and soak for 30 seconds, or just follow directions on the wig shampoo bottle. Since I use baby shampoo I just fill the sink, rinse and wash, then rinse hair thoroughly, make sure soap is out, shake and gently squeeze (don’t be too rough!) then set doll and hair on a dry towel. Comb out hair as described above when hair is damp, not soggy.
(Some information comes from "Justmagicdolls.com" )