I did a search but couldn't find an answer to my question. So, how long after doing a 2 step do I have to wait to do a permanent color? These grey hairs of mine are bothering me and I want to color tomorrow but I did the 2 step yesterday. I'm almost BSL so I don't want a set back. I'm going to use Garnier color in an off black Can I color tomorrow or do I have to wait a week or two?