If you can’t live without styling tools like a straightening iron, protect your strands with a spray or serum. Look for one with dimethicone, a molecule that coats your strands and shields them from heat exposure. TRY: Shu Uemura Art of Hair Brilliant Glaze Thermo-milk, $58, enhances shine and suppleness with a unique blend of refining lipids, goji berry extract and musk rose oil. No. Washing removes the natural layer of oil in your hair, which protects your scalp against the chemicals in the dye, according to Kitty Lai, salon director, Botanics Hair Creation & Hair Spa. Direct contact with these chemicals can result in a stinging sensation on the scalp during colouring. It’s best to wait 72 hours post-colouring to wash your hair as it takes that length of time for the cuticles to close completely and seal in the colour.