Sample background used in tutorial was done for:
The tutorial I promised
Finally got to it, she asked more about the process of design so that's what I did.
I did not tap into the method, but more of the basic concept, and tools you can use to help yourself with.
Every illustrator uses references, heavily.
We don't whip things out of nothing.
Other useful tutorials, sites mentioned:
Stock photos: [link]
When to check your perspective: