I can get cracks so far from head down,
Neck; kind of the back of my neck.
Spine; I can crack mainly my lower back alot by using a low chair or having someone walk on my back or even stretching side to side with slot of pressure but I can also crack my upper back with assistance by stepping on it.
hands; All 3 of each joint in each finger, (knuckle by putting pressure on the base of my finger, mid by putting pressure on the second strip on the finger, and then the tips by holding the the top knuckle firmly and twisting), and the two joints in each thumb by pushing down (1) and then pulling (2).
Knees; by going on my knees and adding pressure to them
Ankles; by standing or laying and holding and pushing foot back all the way, or sitting on the floor and sitting on my feet.
Toes; all the toes by pulling, OR by tightening my toes and then releasing while stretching them which both usually I gets me 1-2 cracks from each. The big toe I usually firmly yank to the side and it cracks.
These are all usually deep cracks.

Other then that I get pops and cracks all over my body while just breathing lol so

I haven't figured out to do any others but I want too!