UCR, is there a correct way?

[LowTech]

I’ve never had a UCR, all me wondering and guessing
Some things that reduce chances of UCR failing and lowering you to the ground.
Have an adequate length of bury
Milk the bury
Use a small diameter cord at far end of bury tied in a prusik or klemheist to help prevent any motion from loosening bury

Outer part of bury or sheath 7/64 amsteel
Inner part of bury or core 1/8 amsteel!!!
Hard to splice, but it can be done—and your UCR will have a death grip, hanging on for dear life…never letting go

Quick field fix, if your UCR lets you down while on a camp out.
Set UCR and hammock suspension close to desired height
Milk bury
Tie bury in a tight overhand knot, tightening overhand knot and milk bury again on both sides of overhand knot.

If you cant or don’t want to disconnect hammock from suspension
Set hammock close to desired height
Milk bury
Tie marlin spike hitch in bury
Tighten MSH and milk bury again on both sides of MSH

The toggle used in this application must be strong and crushproof (no twigs)
Also toggle must be smooth, not sharp so it’s ends do not cut your tarp.
For toggle, you could use a carabiner or a spoon or even some wadded up rope or strap or a stinky sock rolled real tight

Also after setting UCR and milking bury, there will be loose amsteel hanging down at bury exit. You can tie a slip knot in loose amsteel about an inch from bury exit. A slip knot, not to be confused with a slipped half hitch!
If UCR slips, it will slip only that one inch—the slipknot is too fat to travel through bury!

Good luck

If I got paid to tell lies
It just wouldn’t be as much fun

Most of the basics you list I've already done except the knotting and as others have said, it defeats the purpose.

The splicing w/ a smaller over a larger line I found interesting when you mentioned it on another thread. Of course all my splicable line got used making up dogbones and shackles so that experiment will have to wait.

Oh, and I don't have an issue of it slipping. Well once when it was new and the line seemed really slippery, but once I got it a bit "dirty" from use that stopped.