The warm toned areas are beads and the majority of the blue areas are hole punch dots from recycled packaging. In either case, I place each one individually using a straight pin as my paintbrush. The desert floor is made of strips of paper which I drag across some glue and spread it with fingers - kinda like papier mache. As far as random color in the blue areas, I must pick them up from the back because I don't want glue on the surface, it makes a dull foggy appearance. Since I grab ones that are face down I have no idea what color it will be aside from the fact that all the dots are some variation of blue. I embrace the randomness unless I start getting too many similarly toned ones in a bunch.
You can see it very close up on this page:
Now I am seeing who W Edwards Deming is :-)