This is a model I made of the Pod companions from the game Nier:Automata. The elbows and fingers are connected by articulated ball-and-socket joints, and the elbow-to-body connection can also rotate as well.
I printed the body and arms with supports and raft to be safe, while everything else minus the head and stand was printed with supports and brim. The orientation they appear appear by default in the STL is the orientation in which I printed them. I noticed that the sockets worked better when they were printed in a way so that they were standing straight up, so maybe that's something to take into consideration.
Here's what I printed each part at:
Head: 30% infill
Body: 100% infill (this was probably overkill, but I was having issues with sections breaking)
Arms: 40% infill
Everything else: 20% infill
I originally had issues with the elbow-to-body joint being very loose and falling out. I edited them and as they are now, they will probably be printed a little too big to fit right away. I manually filed them down after printing until they are just small enough to squeeze in there and fit snugly if done correctly.
Connecting the head to the body
The body does not have any joint to connect to the head, it must be glued onto the platform. Personally I used Testors "cement for plastic models" to attach it and it works great.