Q: Is it true that I should not shampoo my hair for a few days after dyeing it in order for the colour to last longer? What should I do if I still want my scalp to feel clean?

A: It is perfectly fine to wash your hair the day after having it coloured, says Sunny Lee, international director of Shunji Matsuo Hair Studio.

Hair colour sets while it is processing on your hair and to remove the residue, your stylist washes it off with shampoo, which means your scalp would already have been cleansed.

You could even wash your hair again later in the day after your colour session if you like, Lee says.

Just be sure to use a shampoo meant for coloured hair, such as Goldwell Elumen Wash ($26) or Kerastase Reflection Bain Miroir Shampoo ($38).

Such shampoos help to maintain the intensity and shine of your colour job because they tend to be richer in content and have higher moisture levels than normal shampoo.

Lee suggests you use such shampoos for three days to a week after colouring your hair and revert to your regular shampoo after that so as not to overload your hair.

If you have an extremely oily scalp, steer clear of shampoo meant for coloured hair as it may aggravate your condition.

Using cold water in the final rinse also helps to seal hair cuticles and lock in the colour.

Another tip for extending the shelf life of your dye job: When you revert to normal shampoo, pick one that is low in sulfate, a chemical that strips hair of essential oils and colour.

You can consider something like La Soie Silk Essence Shampoo ($75), a sulfate-free organic product that helps to maintain shine.

Also, treat yourself to a hair mask like Kerastase Reflection Chroma Reflect Masque ($69) once a week to provide deep conditioning to colour-treated hair.

This article was first published in Urban, The Straits Times.