Youtube has excellent tutorials. If you don’t understand it from one teacher, often you’ll find another where it just clicks for you. One alternative for knitting with double points is using a circular needle and magic loop.
Contrary to what some knitting directions tell you, you don’t have to switch to double points from circulars like when knitting a hat. With my circulars, I can get down to knitting two stitches. I do I cords with my circulars all the time. I think they tell you that so you’ll go out and buy more needles for the project, more profit for them. I have one set of Knitpicks interchangeable Harmony Wood needles. They all store neatly and compactly into a small case. I lost most of the double points a long time ago. I keep a few of the stray dps in the bottom of my knitting bag for three needle bind offs. That reminds me, I should bring all my straights that are sitting around gathering dust to a thrift store one of these days.
I do everything on circulars, including straight knitting. I like them because you can push your work farther onto the cables when you’re done with your project for the day and don’t have dropped stitches. I don’t have double points falling out onto the floor when I’m knitting. Since both needles are attached to the cable, I’m not digging lost needles out of the sofa.