At least this tutorial is simpler than the other one, which involves folding specific corners over other corners.
Although I think OP’s struggle is getting the sheet to fit on the bed itself. IMO it’s better to get one that’s slightly too big than slightly too small, since you can tuck the excess under the mattress.
If the excess really bothers you, there are also these little straps you can buy with little suspender clips on either end, and you can use them across the corners to snug up your sheets. I had some knit jersey sheets once that would not stay on until I got some of those.
I got some for my partner because his sheets kept coming off and putting it back on was often something I would do because it was a task that took a disproportionately high level of mental energy for him. Before I got them, he was like “it’s fine”, and handwaving off the faff of putting the sheet back on, because it was just something he was used to. Afterwards he was like “oh my God, what a quality of life improvement from something so small”
How you say? This way:
Do I do that? Heck no
They said fit right, not fold right.
At least this tutorial is simpler than the other one, which involves folding specific corners over other corners.
Although I think OP’s struggle is getting the sheet to fit on the bed itself. IMO it’s better to get one that’s slightly too big than slightly too small, since you can tuck the excess under the mattress.
You just go clockwise.
If the excess really bothers you, there are also these little straps you can buy with little suspender clips on either end, and you can use them across the corners to snug up your sheets. I had some knit jersey sheets once that would not stay on until I got some of those.
Edit: These thingies, sheet stays

I wish I’ve gotten these sooner, feel like they’ve improved bed comfort and sleep quality
I got some for my partner because his sheets kept coming off and putting it back on was often something I would do because it was a task that took a disproportionately high level of mental energy for him. Before I got them, he was like “it’s fine”, and handwaving off the faff of putting the sheet back on, because it was just something he was used to. Afterwards he was like “oh my God, what a quality of life improvement from something so small”