I just tied up a couple dozen leaders so I’ll pass along a few observations and some of my experience that you might find helpful if you want to tie your own.
Here are the specs for the materials used:

Nickel-Titanium Single Strand Leader Wire
25lb Test - .014” dia

Eagle Claw Lazer Powerlight Swivel
80lb Test – Size 6

SouthBend Ball Bearing Coast Lock Swivel
B/BISS-1    35lb Test-Size 1
B/BISS-0    20lb Test-Size 0

Tied using 5 half-turn Clinch Knot

Here are the tools I used:

2 ea needle nose pliers
1 ea side cutter pliers
2 ea 5” pieces of coat hanger wire
*Safety Glasses*

One thing I noticed is that the new batch of wire that I received is thicker. Previously 25lb test wire was .010” dia and the latest batch that I just got is 25lb test and .014”dia.
It’s a little thicker obviously and a little stiffer to work with but I used the same clinch knot and it made a nice leader although slightly more visible than before. In the future I will likely downsize to the smaller diameter.
A few things I found out while tying.
-Work on a white background in plenty of light.
-Leave the stuff coiled and pull out just enough for the first leader you want to tie. Make the first knot and only draw it up snug, don’t try to pull it tight yet. Pull on the tag end only with a pliers, you don’t want to crimp the leader part. Cut off the length you want plus 2-3” then tie the second knot on the opposite end to the snap or swivel. With both ends tied and snugged grab both tag ends with two pliers and draw the knots tight – when the wire stretches (you’ll clearly feel it) you are done. Trim off tag ends close to flush with the knot and then do a final test pull using a pair of 5” wires (sections of a coat hanger will work) through the very ends of the finished leader. You are testing the overall integrity of the leader now so make sure you pull from the very ends so that all of the hardware gets tested under load. I had one snap fail doing this but no knots.
-16” of Nickel Titanium wire will yield a 13”-14” leader. The minimum waste I could achieve was 3-4” per leader.
- The most efficient and useful knot I came up with was the clinch using 5 half-turns. This produced the strongest and tidiest knot with the small terminal hardware I selected.

Thanks KF I was using 8 half turns and 5 would make it easier to get a neater knot. So far just learning using some 15 Lb Swivels.

up KF

The reason I harp on the quality of materials and the longevity of components is because these leaders last for such a darn long time. Unlike standard cable style leaders that become kinked gnarly garbage after a couple of feisty northerns or trout. I would typically use about a dozen of those leaders per trip. These Nickel-Titanium leaders will handle an amazing amount of abuse and you will find that you can actually wear out the metal components before they kink or become twisted.

KF
I have taken some snaps off of the swivel and put then on the other end of the leader.  The Coast Lock Swivels look difficult to reuse the snap.  What do you use for a snap or are you putting the swivel on the lure end of the leader.