Attaching the Drill to the Bowstring
1) holding the drill in the left hand with the blunt end facing the bow, place it under the bowstring
2) holding the drill by the upper half, wrap the end of it  around the bowstring toward you 
3) pull the drill upward and toward you
4) the drill should be on the outside of the bowstring, not between the bow and the bowstring
5) with fingers wrapped around the bow and the drill, move it to the notch in the fireboard. Many of my students have a difficult time getting the bowstring wrapped around the drill. It requires a fair amount of strength. It's nearly impossible to do if you don't hold the drill by the top half. Practice this with the bowstring loose, at first, until you get the knack of it. It will, however, be necessary to have it fairly tight in order to turn the drill. Only with practice will you know if it is too tight or loose.
Next: applying the socket