Before answering this question, it’s worth explaining the chemistry behind hair colouring process. When you apply a hair dye, colouring agents lift your hair cuticle. Once it's open, the dye molecules pass into the hair cortex, the layer responsible for your hair pigment. The colour gets locked there for up to 6 weeks until the dye molecules are washed away.
Unlike other colours, red hair colour is made of very small molecules. Because of their size, they are more easily removed by water, especially when you use shampoo. Also, those small red colour molecules are more easily broken by UV, chemicals and harsh hair products.
If you are thinking of going red, this article 'How to dye your hair red without pre-lightening' may be useful for you.
Protect your hair from the sun
UV radiation is the main reason for colour fading. Therefore, you should use hair products that create a protective layer against it or wear a hat.
After having dyed your hair, don’t shampoo for 2-3 days
Wait for at least 72 hours so your hair cuticle can fully absorb the colour. Dry shampoo is your best friend!
Wash less, but with good hair products
Red hair molecules are so small, it’s very easy to wash them out. The less you wash your hair, the longer you keep the colour vibrant. Though when you do wash it, use sulfate-free shampoos and conditioners that are created specifically for colour protection.
Use hair colour refreshers
Every time you dye your hair, you weaken its cuticle. Healthy hair can keep the colour for longer and damaged cuticle releases it faster. Smart Beauty hair refreshers are a budget-friendly option to bring back the vibrancy of your hair colour. Simply apply it for 3 minutes and your red hair colour is refreshed!
Wash your hair with lukewarm water
When you apply heat to your hair, its cuticle becomes porous and can’t hold the colour. Hot water and styling tools can definitely make your red hair colour fade quicker. Try to get used to colder water and style your hair just once a week to keep your colour bright.
Sounds good? Now let's move to a fun part!