Let's see... I'll go in the order I put it on.
The greaves velcro onto their straps. I added an elastic piece to hold the greaves to the straps more securely, while still being able to flex the straps enough to get them on and off, which really helped with how much they tend to want to pop off.
The shoulders are attached to the front with chicago screws: the leather shoulder armor attaches to the breastplate with one chicago screw, the hawk-head shoulder piece attaches to the breastplate with a chicago screw and to the leather via a strap underneath it. It's also supported up off the shoulder by a chunk of insulation foam hidden underneath it. The leather pieces also have a piece of elastic running across my back/shoulders to keep them from popping forward--this was something I added after the first day's wear and it really helped. The stomach plates are attached (again, with chicago screws) to strips of leather which attach to the breastplate, this allows them to move across one another for pretty decent flexibility.
The back and waist pieces are attached together by a loop of elastic hidden under the back plate--it keeps the horseshoe shaped piece attached to the waist from popping to the outside. The back plate attaches to the breastplate with velcro at the shoulders and sides. The leather belt closes at the waist over top of the lowest piece of stomach armor with another chicago screw (velcro would probably work here but I like as much extra security as I can get). The codpiece thing hangs off the belt via a bent bit of Sintra.
The neck armor needs to be reworked. Right now it attached with some velcro-type stuff (dual lock? Something like that, it's not fuzzy like velcro) in the front and just kind of sits there in the back. I had L-brackets on the breastplate at each side of the neck to hold it in place but removed one of them because I thought it might be contributing to my shoulder pain and now the collar doesn't sit quite where I want it. I think I just have to make a new one with a better attachment.
The bracers go on same as the greaves, with the addition of a bit of leather that goes across my palms to hold the hand guards in place. The hand guards attach to the bracers with strips of leather as well. The bear fur under them is just a tube sewn to roughly the shape of my arm and pulled on over my gloves before putting the bracers on.
And... I think that's it. The most annoying pieces to attach were those shoulder things. Tricky to get them to float just where they should be.