Here's a picture of my rope traveler.
I tied a stopper knot in the line and ran it through the eye strap on the starboard side. Then up through a block and back down to the block and cam cleat on the port side. This allows some adjustment for clearance of the tiller. I then tied a line to the block and can adjust the boom where I need it. Then I tie off to the existing dock line cleats on port or starboard.