has a block near the bow and cleats just outside the cockpit (stern cleats on Lucia) and a carabiner attached to the end of the boom. I run a line that runs from port side cleat through the block near the bow back to the stbd side cleat. At each end of the line I tie a bowline just big enough to drop over the cleat. This is where the line lives when not in use. Having decided to broad reach or run I take the appropriate side of the line, e.g. port side on stbd tack, and snap the bowline end to the carabiner. Once I am happy with the point of sail and sail trim, I tighten the end of the line still available to me and cleat it off. The is done with out ever leaving the cockpit. It also has the advantage of not being in the position of having the main trapped in the water if it all hits the fan for some reason, as with this set up the boom is not trapped down but can rise a bit.

When I jibe, I first release the cleated end of the preventer, center the boom as much as possible and switch bowlines. Then I jibe, set the new direction and sail trim as desires and then tighten the preventer and cleat it off. Works every time and is easy as pie for a single hander, even in a sea way.