Here's how I hook my harness up to my CTX.
Some good smaller diameter cord-- I used the stuff Dloops are tied into bow strings. Not too thin though,,,don't want to damage the fiber in rod.
Mine is wrapped 4 times around shaft,,tying off each time-- to equalize pressure and place pressure over a wider area of fiber.
I used a big white tie strap,,a person could use black,,this will definitely keep the cord from sliding up the rod.
I use a small harness,,can be bought through some of the sponsors here,
This will definitely make your CTX more enjoyable to hunt with, especially on longer hunts.
I use an over the should type harness made by this company in the link.
A type S of one of these,,,very good clearance between control head on CTX and harness attachment.
Pretty cheap, yet effective-- can be removed in a flash if the need arises.