This was simple to use, wash hair twice with clarifying shampoo, dry to 80% and apply the treatment in sections, cover hair in plastic wrap & wait 30 mins, blow dry & then flat iron. I went over it 7 times on each section, took me about 2 hours to get done. My hair feels really smooth & is shiny and smells heavenly like vanilla. Really pleased with the scent of the product & there's still plenty of the shampoo & treatment left over, I'm wondering why they say don't use leftover. Will review again after first wash.