This is one of my favourite kinds of graffiti. I have done a lot of pictures like this before. I even had my sketch-book. I agree with Katya that graffitist should do a sketch before doing graffiti on walls. It's really helpful because you will have a pattern when you'll start painting on walls.
I believe that true graffiti artist should draw a sketches and only then to transform it on the walls. In my opinion this sketch would decorate some urban street. I am sure a painter of this sketch expresses his extraordinary feelings and thoughts. I would like to see this sketch in a larger size on the wall !
I have never had a talend of painting on walls, but I'm good at drawing on paper. Moreover, I have painted such images as this one before. It's not so difficult and costs less. Also, this painting doesn't defaced somebody's property.
I think that it isn't necessary to draw sketches, but it is helpful. It is easier to do a graffiti when you have some certain image in your mind or on paper.
