I found that for me, the best way to practice was to just keep working up yarn, undoing it, and working it up again until I got the hang of it. This is especially true with the foundation chain where you want to be sure that your stitches are as consistent as possible. The tension can be tricky to master which is why it's so important to practice.
If I am working with a yarn I'm unfamiliar with (such as a lightweight fingering yarn that is super thin), I often make a chain, undo it and redo it several times until I get the feel for working with that particular yarn. Even the difference from a weight 3 to a weight 4 yarn can feel so different as you're working it so practicing is absolutely fine and recommended.
In this beginner video, I share how to make a slip knot and how to work up those foundation chains. Lots of repetition and practice is encouraged!
Grab your yarn and your hooks and let's go!