How many hour should a teeneger keep their foam roller?

this my firs time trying on foam roller and I don`t how do I have to keep on. my hair is wet right and I have the foam roller on my hair wrap in a hair blanket. I put on the foam roller on my hair at 7 : 00pm but I watch my hair at 3pm . the reason I took too long to put on foam roller it was because I was taking a shower and then I went to buy them. please answer this questions as soon as fast as possible.
Asked Apr 22, 2014

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