* Natural Oils Protect the Scalp: The natural oils in your hair act as a barrier, protecting your scalp from the chemicals in the bleach or dye used for highlights. This can help reduce irritation and sensitivity.
* Better Grip: Slightly "dirty" hair has a bit more texture, which can help the color adhere better.
* Professional Preference: Many stylists prefer working with hair that's a day or two (or even three) since the last wash. They often find it gives better results and is more comfortable for the client.
However, there are a few caveats:
* Product Buildup: If your hair has a lot of heavy product buildup (hair spray, gel, etc.), it *could* interfere with the highlighting process. In this case, a light clarifying shampoo a few days before might be a good idea.
* Excessive Oiliness: Extremely oily hair might make it harder for the stylist to section the hair properly. Again, a light wash a day or two before could help.
* Specific Recommendations: Your stylist is the best person to advise you. If they have specific instructions for how to prepare your hair, follow their guidance.
In summary, aim for hair that's one to three days since its last wash, and avoid excessive product buildup.