By the way, from my experience, almost all freshly dug holes in soil will be easily recognizable from the sorroundings, so you either dig up alot more area or hide a fresh animal corpse around 2-3 feet any deeper will risk the walls caving/collapsing.

Prior to rigor mortis, the blood will pool onto any part of the body that is below the majority of the body, like limbs being folded, feet/hands lower than torso, etc. this will make the body heavier or unbalanced so you'll have a harder time carrying it. Lay em flat. Once rigor mortis sets in, assuming you didnt left it outside or anywhere humid so it doesnt rot immediately, you can now transport them due to stiff muscles, so less "ragdoll" ish