Do not strip the cable. Cut it with a sharp instrument, I just use sharp scissors and make
sure that the cut is flat, you can trim it to make it nice and flat.
Back the set screw out, far enough to allow the cable to pass. Put the plug on cable and push the plug onto the needle. It will stop when it hits the needle, and if you push further
it will go another 1/8" or so, then you know the needle is in the cable. This is your hot connection. Tighten the set screw down to touch the cable. Then tighten the screw 1 1/2 - 2 rotations. This is the ground connection.
Right angle plugs:
Remove the top and insert the cable, pushing it onto the needle. Bend the cable over into the slot (not really a hard bend, just enough to get the top on) and replace the top, screw it down completely, you can use pliers so it won't loosen.