A practical guide for Malachain readers, written from everyday experience.
One scarf teaches everything a beginner needs: casting on, the knit stitch, keeping tension even and casting off. Choose a medium yarn in a light colour so the stitches are easy to see, needles a little larger than the label suggests, and a width of about twenty stitches. Knit a few rows every evening and the first lumpy inches soon become straight.
Mistakes are part of the fabric, and most of them disappear into the pattern once the scarf is worn. Watch one short video for each new step rather than a whole course, and knit in front of the television so the hands learn without the mind interfering. By the end of the scarf the movements are automatic, and a hat or a pair of simple mittens is a short step away.
It also helps to talk the subject through with friends or colleagues who have tried something similar. Their experience points out the details that guides leave out: how long things really take, which costs were unexpected, and which shortcuts turned out to be a mistake.
There is more to learn on this subject, and the linked website goes into greater depth. Treat this article as an introduction rather than the final word, and check any important decision against up-to-date, reliable sources before relying on it.
If you try any of these ideas, start small and adjust them to your own situation. What works for one person will not suit everyone, and it is fine to keep only the parts that help. Writing down what you changed, and what happened, makes it much easier to see after a few weeks whether the effort was worthwhile.