Since I'm such a beauty junkie and because my hair rarely gets to rest from all the blowdrying, hair straightning and tough hair styles I have tried most hair masks out there. This one by Kerastase called Age Recharge is by far my favourite. On the label it says apply to towel dried hair and leave for 5 minutes. I tend to leave it for longer than that. Usually (if I have the time) I apply it and wrap my hair in a hot towel, and leave for a few hours. Every hairstylist who's done my hair since I started with this mask has complimented me on how soft it is. And they should know! It's not the cheapest one out there but it lasts a long time and I would suggest browsing the internet to find cheaper prices than at the salon.