I'm a side sleeper with a bad back. Over the last several years and testing 7-8 pads I've learned the following:
1. First night out always sucks. New bed, noises, temps, bag vs blankets, etc.
2. I need a 25" pad, 3.5"-4" thick.
3. Longitudinal tubes work better for me than horizontal. Horizontals destroy my back.
4. Inflate to about 80%. Just enough to keep my hips off the ground. I fill to 100%, set everything up, lay on the pad, then deflate to comfort level.
5. Put something 2"-3" thick under the pad about where my knees or lower legs are. This helps simulate the crater at hip level in a regular bed and keeps my back aligned. I have used an empty backpack but now have a 25" S2S pillow.
6. Wear long johns, even in the summer, to eliminate the feeling of nylon on skin.
7. Fold pants to about 2" thick and keep between knees to help keep my back straight.
8. With an air pillow, inflate to 50%-60%, put it in a cotton pillowcase (mine is half size) along with spare clothing. Make sure to smooth out the wrinkles.
9. Earplug in upside ear, switch when rolling over. Plug in downside feels like a nail in my ear.