Starting from scratch, I tie an adjustable nocking point that threads up and down the center serving. I use serving material in the .025-.030" range, tied in a whip knot, in the same direction as the center serving with around 6 loops. 3" material makes one knot, but you need approx. 8" or so working length to pull the tag ends. Once the final nocking point is set, a dab of superglue locks it into place.
If I already know the perfect nocking point height, I may merely tie one into place using dental floss. But, if materials are at hand, it is still easier to whip tie an adjustable nocking point, which can be thread up and down the center serving, to ensure the nock point is exactly where it need to be prior to locking it into place.
I completely dislike crip-on brass nock points, and I prefer a single nocking point set for "Hill" style nocking over.
Best