Starting grey wash

Hello, i am thinking on learning how to do grey wash, my inks are fine bow im stuck on how to and where to start.

Should I fill my design first with my lightest and just blend it with the mids/dark? Or should i start with the mid? Etc

I don't think there is a right way to do it...just has to be what works best for you. Here is a video to watch, maybe it will give you some ideas.