You pretty much find the " spot" the same way that you would any other nocking point. Fine tune as usual after that. Make sure that you tie the two knots on opposite sides of the string. That assures that there is even presure on the right and left side of the nock and helps eleminate any tendancy for the arrow to rotate left or right at full draw.

You do not need to tie in a nock above or below or put in any brass nocks to help " hold" the loop in place. The loop will sinch down around the serving and will not move on you. If you need to move the loop up or down then just rotate it around the string.