I bring a book and my sketch pad whenever I go to a place where I may be waiting. I have been limiting my sketch time to 15 minutes, which is long enough to fill an 8×5 inch sheet of paper with scribbling that indicates a sense of my visual environment.  If I find myself waiting more than 15 minutes I can read a bit.

Two Thirty-Five
5.5″x8.5″ 138# Mix Media