Get a job digging ditches in the construction industry. You'll make money whilst training
I know it sounds stupid but at my job I have a lot of heavy stuff around. I am a forklift operator, so I can grab that always.. but sometimes I opt to just lug it myself. Dragging big ass boxes full of Ductyl Iron pipe fittings, putting heavy shit onto big shelves almost like World's Strongest Man rock lifting, etc. Obviously you want to be careful and don't hurt yourself, but I think the general idea with "caveman training" is to use an all inclusive body movement exercise. See tire flipping post above (which is a funny post, btw) and also the swinging and loading of shovel after shovel of dirt.
Best bet is to hook up with someone who is certified to teach these specific techniques and to push you through them.