The best thing top remember about the skeins that chenille comes on is that you can not tie a true knot in them unless it is by taking the end and doing so. I have unraveled skeins of yarn and chenille before and as long as I didn't untie anything right away by removing a knot with the end of the chenille I was fine. It is a pain in the arse but can be done if you never pull hard enough to make anything too tight to simply pull the loops out and slowly unravel it.

Any tangle, don't pull on it, find the loops and remove them to untangle it. If you find the end, try not to ever use the end the end to get out a tangle because once you do you will have a lot more true knots. Only untangle with the actual end when you have to and is the last resort. Get a crochet hook to get tighter tangles out and to pull the chenille lose to pull out the loops to untangle it.

Can't think of anything else but will post it if I do.

If kinda like this, take a rope, put the ends together and tie it in knots and loops and everything else you can think of. Then untangle it and never let the ends come apart. Then do it again and untangle just a little of it after you let the ends come apart and pull and end through a tangle. It sounds weird but it makes a huge difference.