These are all wonderful tips, and I have one more ... :)
Poor DeafBlindPossum, full-blown CCD spins relentlessly (although we have seen a huge decrease with behaviour modification ((interruption)) and finally an Rx) on some good advice from Animal Trainer, AlphaDog, we got her the Gentle Leader Harness. NOT the head harness, the saddle harness. The D ring is in front at chest level. She walks on a perfect heel. In fact, both she and DeafblindGabriel on a coupler walk on a perfect heel. The true test will be with AllicksBlindPup who sails through life at 120 mph. I haven't found one large enough for her yet, though.
I cannot recommend highly enough the Gentle Leader Harness. Our local rescue started using it with their very large, headstrong, never walked on a leash before, rescues. It works.