Even with YouTube videos, I feel like my knots don't look exactly like the ones in the videos...
There is a thing called "dressing a knot". This means you massage and adjust the rope a little after you've finished tying the knot to make it look pretty. It'll still be the same knot, just neater.
If you struggle with tying knots, I would suggest you start by doing it in the
exact same orientation as shown in the tutorial.
The key is to pay attention to what parts go under or over what parts. If you can correctly identify the parts the rope has to go over (or under) as you're tying the knot, there is a good chance you're tying it correctly, even if it doesn't look exactly right at the first sight. Once you're finished, try to adjust it a little and see if that makes a difference.