Today I'll be sharing with you an awesome technique for adding graffiti to walls in your MOCS. The technique is by Roman on Flickr: https://www.flickr.com/photos/akunthita/galleries/72157647564991497/
The effect of spray paint on the surface has been created by building plates in both directions. There are a number of ways to do this, but the most common that Roman has probably used is building the plates vertically by also building the wall vertically. The horizontal plates that create the yellow and red outline are most likely connected to a back wall or just slotted into place.
What adds further detail to the MOC is not just the accessories surrounding the graffiti, but the discoloured greys used for the wall and floor. This adds a variety of colours instead of just being one solid wall of grey and shows of the plates used.