Mine came with clear instructions, but yes you've got the idea. It is important to fit them the right way round as well, with the moving part of the valve pointing toward the bottom of the pole. As far as the JG fitting is concerned, fit the uni-valve in such a way that it stays in the pole when you change the brush. I have a JG 'T' piece at the top of the pole with the plastic hose end that pushes into it. This stops the hose pulling down the pole and allows easy change of the brush.
Hope this helps