Ed's video is a good loop knot for attaching the OPST skagit head to the shooting line, using the same knot at the other end would be fine also, you would put a bimini twist loop in your backing and create a loop to loop connection.
Or you could use a knot like the slim beauty or fishermans knot to join your backing to the OPST lazer line (this line ties awesome knots), I use the later, very very strong knot, used in deep water jigging and heavy popping for gt's etc, snugs down super small and slim, can use glue if you like but if you form it slowly and properly it doesnt budge.