I tried for several years to make my own hip belt for my home-made external frame pack. I always ended up with sore hips -- on my JMT trip my home-made belt actually led to open wounds on my hips. I finally broke down and ordered a hip belt from Bruce at Luxury Lite. It was easy to install (it just Velcro's around the bottom rung of my pack), is easy to adjust and transfers weight perfectly.
My blog on politics, the environment and the outdoors: Haiwee.blogspot.com