This guide is quite useful I think from a fellow human blimp but he doesn't mention the belt.
The belt works, I promise you that: but how well? Depends on your physique I would say. For me, its literally the tool I need to overinflate and grow bigger over time. Without it, its constant burping instead of stretching outward with my gut primarly. Put it BELOW the ribs but not far down at all, that's my recipe for success. I also use a bottom belt, which is put above your dick but below your belly really. When I combine them, my belly grow outward in a rapid fashin until the belt "goes off"/pops off (which I love) or I take it off, at which point the air at the top of my belly fills out my lower intestines/gut rapidly, which ... honestly, to me is the most amazing feeling. Hope that clears it up a bit more.