Bleached for 1 hour at room temperature, covered with plastic cap. Toner is silver so if you want a platinum blonde tone your hair needs to be almost white prior then only process toner for up to 8 minutes. If you process toner longer than 8 minutes you will likely have silver hair as long as your hair was previously bleached to almost white. LTKOver40 LTKStyleTip LTKBeauty