Before I answer, please note mine is a 2014 XC60. Volvo redesigned the knob with two thin wires compared to the tape wire on yours. I previously changed the knob on my S80, so thought it would be just as easy, but it was not.
To remove the knob itself, you need to turn the leather collar 1/4 turn counter-clockwise, then pry the front and back plastic tabs slightly to release the knob while pulling up. The wire is secured under the leather boot by a zip tie. To remove the leather boot, I needed to unscrew the console with the cup holders. Then there are two tabs under the boot at the top and two at the bottom that you push to remove the boot.