You are not going to ruin anything 'cg' by shampooing before colouring.
Permanent colour and bleach is a zillion times more damaging than one application of shampoo. Semi permanent colours often have surfectants built right in, so whether you like it or not, colouring your hair is going to get stripped from it's natural oils.
It depends on the type of colour you're using as to whether it will be affected much by the gel. Also depends on how much gel. I would tend to wash it first, but if using permanent colour and not much gel, then going ahead without shampooing is probably just fine.
Shampooing is important to everyone's hair care schedule, regardless of hair type or texture. You should shampoo as generally as necessary to keep your hair looking clean and your head relaxed. Those who have oily hair, exercise daily, or live or work in unclean environments may require to shampoo daily, while others need to shampoo less regularly. Twice a week is generally enough if your work does not involve any physical task. It is necessary to secure hair from the damaging, drying benefits of the sun. If you swim, be sure to quickly shampoo your hair remove chlorine and other chemicals, or salt water, all of which may effect in drying. If you have slimy hair, you will need to wash them regularly say twice or thrice a week.
Seriously, you are not up to date on your information.
The vast majority of shampoos are damaging to hair and scalp (and the environment). Many people here use a no shampoo method of cleansing their hair with no-silicone conditioner. It works beautifully and since I started this regime my hair stopped breaking and I finally have increase in length!!
You've been brainwashed, just like all the rest of us sheep. Time to open your mind to some real options in healthy living and inform yourself!!
Our society has been fed sooo many lies about sooo many things. It makes me sick!!
Unless it's a temporary dye or pure henna, it will likely say to use it on 'dirty' hair, which helps protect from too much damage. I would not shampoo before dyeing my hair, especially if it is not part of my daily hair care routine.
When I was at my old salon but was beginning to use the Deva products, my hairdresser asked me what was in my hair. I told her - the Lo Poo, the One Conditioner, and the styling creme. She said there was no way she could highlight over these products because they are so thick that the color would not completely get through or stay in. She had the shampoo lady wash my hair first.
Have any of you ever heard of this? She was very good with color, but this was new to me!
You don't have to shampoo before or after. Your normal cowash or low poo should be fine afterwards. I never shampoo after using chemical dye or henna and the color always turns out great. Dye or bleach can penetrate the hair shaft even with 'goop' on it.