We generally went for walks 2 weekends out of 4 anyways. But that was about it, and these were not strenuous walks. Maybe this was naive in the extreme. The longest walk we did before the hike was around 11 miles, and there was no real elevation gain in it.
If breaking in the boots and socks we bought counts as preparation, well then we did some.
Dad carried his backpack with a couple of 5 gallon bottles of water to adjust the pack, walked to the Apple store in Manhattan and discovered that a bottle was leaking. Dad also slightly ruptured his achilles doing this, swelled and caused enough discomfort two weeks prior to the hike that Dad bought a compression sock which was worn religiously until we returned home.
We didn’t try any of the dehydrated food, we just bought what was really the best deal out there.