Know how to use your equipment, before you need to use your equipment. My power awning can be manually tilted and has auto dump. I learned how to use both before I needed to use them. Just like knowing where your jack and spare tire are, before you get a flat tire on the side of the highway.
For that matter, how many people know if their trailer tires have a different size lug nut than their tow vehicle? Mine is different, so I carry a 4 way lug wrench in my trailer. My buddy had a flat earlier this summer and did NOT have a lug wrench for his trailer. Luckily we were in a group and someone saw him and stopped to lend a hand/wrench.