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Deep condition Strip away existing dye and color with a clarifying shampoo. Do a strand test to see how the bleach takes to your hair. Divide your hair into 4 sections with elastics or clips. Protect your skin and clothes by wearing gloves and an old T-shirt.
your hair every 2-3 days for 2 weeks before bleaching it. This isn’t required, but it’s helpful if you have the patience for it. Going from black to blonde hair is going to require several bleaching sessions, and bleach easily dries-out and damages your hair. Get it to the healthiest state beforehand to make the result look that much better. Similarly, stop using heat-styling tools for a few weeks before bleaching to limit damaging heat exposure. Please note that if your hair hasn’t been color-treated, you can skip this step. Clarifying shampoo won’t completely remove the color from your hair, but it can lighten it enough to make it easier to bleach. Use the shampoo for 2-3 washes before you plan on bleaching your hair. Avoid using clarifying shampoo the same day you apply your first bleach treatment. It could cause your hair to get excessively dry. This test will help you determine how long you should leave the bleach on your hair for. It could also tell you if your scalp is too sensitive for the bleaching process. Use a small section of hair that is at least 1 inch (2.5 cm) wide and that can be easily hidden underneath the rest of your hair.  Clip the rest of your hair back so that it doesn’t accidentally come into contact with the bleach. Wear gloves and follow the directions to mix the bleach powder and developer. Leave the bleach on your hair for 30-45 minutes before rinsing it out. If your scalp gets red or irritated, that could indicate you have an allergy or sensitivity to the chemicals. If this happens, don’t proceed with bleaching your entire head. Visit a professional colorist to see what your next steps should be instead. Once you’re ready to start your first bleaching session, separate your hair into 4 quadrants: part your hair down the middle, then split each side into 2 sections, one high and one low. Use hair elastics or clips to keep each section separate. If you have a lot of hair, you may want to separate it into even more sections so that it’s easier to work with. Bleach is a harsh chemical and can burn your skin, so you should limit how much of your skin comes into contact with it. Wear a pair of rubber gloves when mixing and applying the bleach powder and developer. Change your clothes and wear something you aren’t super attached to—if you drop bleach on your shirt, it’ll stain it. You may also want to lay down some old towels to protect the space you’re working in. If bleach gets on the furniture, it can cause irreparable stains.