My favourite method:
Make two short sevings (6-8 mm) on the servings approx where you want your nocking point,use a nail knot to finish but leave the tags a bit long.
Tighten the servings moderately so you still can twist them but not slide them on the main serving,that way you can twist them up or down like on a threading to fine tune them.
when you are happy, tighten hard cut and burn the tags and add a drop of superglue
that will outlive the string itself and look good while adding minimal weight