1. Don't Wash Your Hair Every Day
No, it's not gross. It's actually really not needed, even if you don't have dyed hair. Every time you wash your hair, a little more pigment slips down the drain. Utilize dry shampoo to revive your hair between washes.
2. Don't Wash Your Hair in Hot Water
This was an especially hard tip for me to implement since I love super hot showers. However, heat opens the hair cuticle and allows the dye pigments to slip out. You don't have to rinse in ice-cold water (unless you're rocking fashion colors); room temperature will work just fine.
3. Don't Over-Shampoo Your Hair
Long story short, shampoo is designed to clean the scalp. You should not be lathering up your entire length of hair with a handful of shampoo. It should look nothing like the commercials! Focus on scrubbing your scalp and let the rest get a quick clean as you rinse it off. Unless you just rolled in some mud...then you can wash it all.
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4. Use Professional Shampoo
It never ceases to amaze me that people will spend upwards of $100 to get their hair dyed, yet wash it all down the drain with $4 shampoo. If you're buying shampoo at the same store you are purchasing toilet paper or bug killer...it's not great quality. Most of them aren't even good quality.
5. Use a Good Heat Protectant
Remember how I told you heat opens the hair cuticle? This not only applies to water but also heated styling tools. That's right, your blow dryer, flat iron, curling iron/wand, etc. are all damaging to your color (and your hair in general)!
Heat protectants create a barrier between the hair and the hot styling tool to greatly reduce damage. They seal the cuticle and lock in moisture.