A. Daily treatments keep hair's outer layer moist, while deep conditioners, which contain stronger active ingredients, need to stay on longer (about 30 minutes) to penetrate the hair shaft for more intense hydration to help strengthen hair, explains Kathryn Hamernik, stylist and global educator for Aveda Corp.
If your hair has body and luster, and isn't processed, a daily conditioner may be all you need to smooth the outer layers and keep locks shiny. Be sure to rinse well with warm water, until hair no longer feels slippery, to prevent residue buildup.
If you have very fine, limp hair, you can skip a daily conditioner -- it'll only weigh your hair down.
If your hair is processed (color-treated or permed) or damaged from blow-drying or styling, you should deep condition once or twice a month. Deep conditioning can also help restore moisture and manageability to hair that's naturally coarse, lackluster, or flyaway.
You can turn your regular conditioner into a quickie deep treatment: Apply conditioner to damp, clean hair and work it through with a wide-tooth comb. Then wrap a warm, damp towel around your head -- the heat opens the hair shafts and allows for deeper penetration. Rinse after 10 to 15 minutes.