When I returned to knitting after a long break, I'd completely forgotten how to make a slip knot to enable me to cast on. I watched countless videos on Youtube, to try to master the technique again, but just couldn't manage it. I think I had some weird lack of spatial awareness, which prevented me from reproducing what was advertised as an easy peasy technique! However, I finally found a video (below) that helped my particular way of learning. As soon as I watched it, it clicked and I was immediately able to make a slip knot. I now show this to first time knitters, as I feel other techniques unnecessarily complicate things.