Several people have asked me this, have tried it, and this is what we think we are works best:
First, I would assume that the pain arises from the area on the spine where the nerve emerges, so wherever there is pressure, I would treat the nerve there (in this case, at the impinging area of the spine)
If that does not help, then try locating the coils further and further down the nerve toward the area where you feel the pain. You may need to look up the neuroanatomy (easy to do on the Internet).
How far to move them each time? I would say about 1.5 to 2 coil diameters (3 or 4 inches) down along the path of the nerve.
How long should you leave the coils in each test position?:
Starting at the spine, I would say at least an hour or two. Then, if that is not helping, try moving them down along the nerve pathway from the spine toward where it actually hurts, holding the coils in place at each spot for at least 30-40 minutes. This may work if the nerve impingement causing your trouble is not actually at the spine, but is somewhere further down along the nerve.
You may get relief more quickly. It may take longer. It may work instantly. It may not work at all.
Individual biological variation makes this a trial-and-error process. But with practice you will get pretty good at it.