Always keep a camera with you. We were driving down the road when we came upon this house. This single picture says so much and I would have missed it without our camera. I know I could have used my cell, but my DSLR produces much better pics.
Don’t discount the cell though. I use the voice recorder on it to save thoughts or descriptions wherever I am and inspiration hits. There are several apps available too which provide improved organization of these thoughts.
Don’t get caught off-guard. Inspiration will hit you in the face at the most inopportune time. Be ready for it.