Step 1:  Grasp the hook from the bottom with one hand.  Grab the strap with your other hand.

Step 2:  Holding and twisting the strap in one hand, flip the hook up with your other hand and slide either edge of the strap between gap at the base of the hook.

Step 3:  Allow the strap to bisect the hook.

Step 4:  Slide the strap through the base of the hook until it slips into one of the notches located on the bottom curvature of the hook.

Step 5:  Now slide the remaining half of the strap into the other notch.

Step 6:  Congratulations!  You have successfully stowed your hook.  This stowing process will become easier as you practice.