As soon as I hook up my Jeep GC, I push it away from the MH, so the tow bar arms lock. If I can't push it, I will know either I forgot to put the transfer case in neutral or the parking brake is still on.
I tie a light colored plastic bag on to the top center of the steering wheel. Then I can see if the Jeep's steering wheel moves when I make my first turn in the MH.
Tom, Pat and Buster (the Boston terrier)
2004 DSDP 3807, 370HP Spartan