I do this full time over summer months...
1. When planning routes and busy days, I generally only do shops with which I am already very familiar.
2. I know what I will and will not take for a shop. I don't undercut myself. If I am negotiating with an MSC, I am up front about what I need.
3. I map the order I am going to do my shops ahead of time. I take into account store hours, traffic, etc.
4. I keep a notebook next to me in my car which lists a few basics for each shop (required photos, weird scenarios, target name, any alias information I need). I prefer this to note on my phone.
5. I keep my my phone and PV500 charging in my car.
6. I have a list of self-assign fillers that I could grab during my route in different areas if I happen to get ahead of schedule or have a cancelled shop.
7. As I plan routes, I contact schedulers and let them know I am going to pass through areas that are not typically in my area and ask if they have needs. (If you video shop and are headed out-of-town, there is a good chance that somebody has a shop for you in your destination.)
8. I make sure I have back-ups for anything I might lose or could get broken, etc. (Imagine a long day of video shops for high-end cars, retailers, homes, etc. and then managing to spill coffee on your only video shirt.... Oops.)
9. I plan extra time each day, just in case something goes sideways.
10. I audio record almost everything and take lots of pictures to document observations. Memory aids.
Hard work builds character and homework is good for your soul.