Bleaching your hair can really damage it, but a hair mask can help restore some of the moisture. You can purchase hair masks from most beauty supply stores, or you can use warmed up olive oil and massage it into your scalp and hair roots. Shampoo strips your hair of its natural moisture and oils, so avoid using it too often after you’ve bleached your hair. Shampoo every 2 to 3 days. If you really, really can’t wait to shampoo your hair, consider a spray-in dry shampoo to absorb some of your hair’s oils. Many hair care companies offer a range of products for color-treated hair, including shampoos, conditioners, and hair treatments. Swap out  your regular hair care products for these types of products after you've bleached your hair. It will protect your hair and maintain your color. Some companies even offer products for bleached hair – if you can find an afford those types of products, they're best. Bleaching your hair will dry it out, so applying even more heat can do a lot of damage. Try not to use straighteners, blow dryers, or curling irons on bleached hair. If you absolutely have to, use a heat protectant spray first. Try out some no-heat styles, like braids and buns, or create curls with rollers. Depending on the shade of blonde you want to maintain, you’ll need to re-tone your hair every 2 to 8 weeks. This will prevent your hair from reverting to a brassy blonde. When you hair starts to look brassy or yellow, it’s time to re-tone! Bleached hair can easily begin to turn green when exposed to chlorine. If you can, avoid chlorinated water like pools. If you can't avoid chlorinated water, use a protectant spray designed to prevent blonde hair from turning green. Or, coat your tresses with a leave-in conditioner before swimming so your hair doesn’t absorb the chlorine. You can find those products in most beauty supply stores. Alternatively, you could wear a swim cap to protect your hair.

Summary:
Apply a hair mask every few weeks. Don’t shampoo too frequently. Use products specifically designed for color-treated hair. Avoid using heat tools. Re-tone every 2 to 8 weeks. Avoid chlorinated water.