Ajidahk, I like to start with a clean/naked base. So, I shampoo my hair first, but I don't condition it. I just apply the henna as soon as I rinse. But, that's just the way I do like to do it. Others may have success with other methods. It is considered best to apply henna to clean hair - no styling product, oils, etc. But maybe if you condition with an oil-free conditioner that doesn't coat the hair too much, it would be okay.