If there's one drawback to warm weather, it's that all that time spent outdoors can strip the natural moisture from your hair. The remedy? A deep-conditioning treatment using rich, emollient oils.

Although many oils can be used -- olive is a favorite in Mediterranean countries, while Native Americans used jojoba -- blends are better, says Los Angeles-based stylist Philip B., who created an at-home kit as part of his line of botanical-based hair-care products. "A mix of different-size oil molecules will penetrate and condition more effectively," he explains.

With Philip's help, we've created an easy at-home treatment that gives even the driest hair bounce and shine. Follow these steps, and remember your grade-school science: Since oil won't mix with water, it slides right off wet hair. Don't dampen your hair until the wash-and-rinse stage.

Use a natural, blended oil before brushing for best results (try Philip B. Rejuvenating Oil, Aeto Botanica Fortifying Oil, Better Botanicals Herbal Hair Oil, or L'Occitane Summer Oil for Body and Hair). 

And remember: Oils will penetrate dry, thirsty hair better than hair that's been freshly washed and conditioned. Brush hair thoroughly to distribute its natural oils, and drape a towel over your shoulders to catch drips.

Work oil into your hair one section at a time. Starting at the ends and using your fingers, apply a few drops at a time. Work it into the hair until it's saturated, stopping an inch from the scalp. Pay particular attention to dry and damaged areas, which will absorb more oil.

Using a dryer with a nozzle attachment on a medium-high setting, direct heat down the hair shaft and away from the scalp. If your hair is dry, leave oils on for 20 to 45 minutes. Colored, damaged, or brittle hair will need 45 minutes to 2 hours. For a truly deep-conditioning treatment, leave the oils on overnight -- just cover your pillow with a fresh towel.

Apply a heaping handful of a natural shampoo to dry hair. Work it into the hair and scalp for three to five minutes. If needed, spritz your hair with just enough water to create a workable lather. Rinse with warm water.

Hair is already moist, so a light conditioner is all you need. To remove any oil residue and leave hair bouncy, try a cider-vinegar-based rinse (such as John Masters Organics Herbal Cider Hair Rinse Clarifier). Rinse, dry, and style as usual.