I modified a ladder with folding platform steps to provide a way for my young daughters (currently ages 3 and 4) a way to climb up/down from the pop top:
Storage entails folding it flat and placing it on top of the bed before putting the top down. Our bed platform consists of multiple sections, and we typically travel by stacking the frontmost section on top of the one behind it and folding the mattress back before lowering the top. This sandwiches the ladder against the top and prevents it from moving.
For some reason I was driving the vehicle without the frontmost section stacked one day, and as luck would have it had to make a sudden stop. Since the ladder wasn't pinned between the mattress and pop top, it came flying out and crashed down behind me. Thankfully I was going relatively slow and driving alone without passengers, but it was a great reminder to always make sure things are truly secured before driving!