As a Location Designer on the revival of the classic series, I worked from drawings from the clients and the Production Designer. For a while, I had free reign on how to approach things. So locations were just a refresh of the originals but when Blue and crew go to another place, it was time to experiment! The creators wanted to really stretch with the new locations. Below is a selection of early versions of some of the locations. These weren't designed to be pretty illustrations, but to demonstrate a look (that would be refined later on). I worked from sketchy storyboards and scraps of notes and images and feedback like "I don't know, man, they want a Dr. Seuss feel... have fun!" So I did.
There were other hands adding things to some of these images, mostly to do with textures of the more mundane items, The "weird" locations are all me (for better or worse). After a shake up in the upper production levels, I moved to layout and background painting. I left part way through production, so I don't know how these all turned out in the end but it was fun while it lasted!
During production I created custom textures, layer styles, brushes and patterns. The "cotton ball" clouds were brushes that painted cotton balls from various cotton ball photos. They weren't stamps or photos. I could paint any cloud shape I wanted and it looked like it was made of cotton. An afternoon of experimenting to get it working right. And it was a two-brush process.