I need to tweak something with my harness soon, so I can take some extra pics and post.
In the meantime, I have a fairly standard set up. The clips hook onto the aluminium bar attached to the bottom of the harness. These bear most of the weight.
The white straps (attached to the black straps near the top of the shoulder) go through the flak vest and the slots in the back armour and attach to the hooks mounted on the back of the jetpack (near the top).
Here's a link to my WiP thread. it shows the position of the hooks and clips on the jetpack.
The page before also shows my harness setup.
http://www.thedentedhelmet.com/f20/wip-esb-fett-rapidly-expanding-project-49771/index3.html
I hope that helps, but let me know if you have any other questions.