Going platinum blonde can be expensive. Salon prices are enough to make you back out from making those pastel-haired dreams come true... but not if you're a DIY maven who spends a lot of time online. You'll find tons of hair bleaching and dyeing tutorials that might having you thinking, "Hey, I can do this myself!" Sure, just buy the bleach, mix stuff, and apply it to your hair directly — what could possibly go wrong?

Well, actually, pretty much everything can go wrong. Playing with bleach is risky business that can lead to patchiness or worse, damaged hair beyond repair (we're talking bald).

That's not meant to discourage you — bleaching hair on your own can be really exciting. But you should be aware of the fact that bleach and hydrogen peroxide are harsh chemicals that should be handled with knowledge and great caution. So before you even make the trip to the store, read this and avoid making the worst mistakes when bleaching hair at home.

Image via Imaxtree

Although you might feel like you know everything you need to know after watching two or three YouTube videos, chances are, it isn't enough. And not bothering to do extensive research might just lead to your worst nightmare: Bleaching mistakes can lead to brittle hair and burns or unflatteringly orange-y hair. Suffice it to say, there are lots of things you should know and check multiple times.

First, are you sure your hair is suitable for bleaching? If you have previously processed your hair, you might want to skip bleaching this summer, since it's best to bleach virgin hair (whether you're alone or in a salon) for lesser damage.

Knowing the right bleach developer to use is also vital. The higher the volume, the lighter you can go in one sitting, but also, the harsher and more dangerous it is for your hair — trust us, you don't want to just guess on this one.

Another issue is managing your expectations. For girls with jet black hair, going light blonde after 30 minutes of bleaching is an impossible wish. You'll have to be realistic with the outcome to avoid double processing (we'll get to this later).

Try: Manic Panic Flash Lightning Bleach Kit 40 Volume Cream Developer, $12.99

Even if you're going to a salon, preparing your hair before bleaching is an important step. Having your hair in its best condition helps the bleach perform better and prevents hair damage. The harsh chemicals used in bleaching dry and heat up your hair so you've got to make sure that your hair and scalp is moisturized. Reduce your use of hot tools for at least a month before bleaching to help keep your hair in tip-top condition.

Another important thing to remember? Don't wash your hair at least 24 hours before bleaching: You see, it's actually better if your hair is oily. Along those lines, it's also often recommended to treat your hair with coconut oil before bleaching. It will help the process and create a protective barrier for your hair and scalp against the damage.

Try: Mother Nature's Essentials Organic Fractionated Coconut Oil For Skin, $16.95

In addition to the bleach and developer, you also need to gather the correct tools: You'll need a mixing bowl, dye brush, section clips, and gloves.

One important note: You must NOT use any metallic tools, since they will be burned by the bleach mixture. Instead, opt for all plastic home hair bleaching kit to have a smoother experience. Also, be sure to wear an over-sized shirt that you don't care for (because no one likes bleach stains).

Try: Diane 7-Piece Hair Coloring Kit, $6.37

Most people don't have allergies to bleach alone (though some are certainly more sensitive to it than others), but if you're using a bleach with color in it, patch testing is always important. A day before you apply it, make a small portion of the bleach mixture and do a patch test on the inside of your elbow or at the back of your ear. Wait for it to dry up and watch out for allergic reactions. As mentioned earlier, it's natural for the bleach to heat up. But if it stings too much and starts to burn, abandon the plan immediately and rinse with water.

When you do the patch test, go for a strand test as well. This way, you'll have a realistic idea of how the bleaching process will go.

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