Cố gắng không để chân tóc mọc quá dài. Chuẩn bị hỗn hợp thuốc tẩy. Thoa hỗn hợp lên chân tóc khô, chưa gội. Kiểm tra tóc thường xuyên. Gội sạch hỗn hợp tẩy trắng trên tóc. Thoa toner cho tóc. Gội sạch toner trên tóc.

I'm interested in that, but I only have a few mins. Can you give me at most the first 500 characters of a detailed explanation in English about that?
Try to renew your bleach when your roots are an inch at the longest. This will help keep your hair looking more even.  If you let your roots grow longer, it may be more difficult to touch them up without having them clash against the rest of your hair. Since hair grows about .5-inch (1.25 cm) per month, you will likely need to do your roots every two months. This will be the exact same process as when you initially bleached your hair. Mix the lightening powder with the developer on a 1:1 ratio,