Use your thumb on the same hand pressed at your fingertip to hold the yarn in place.
Once you’ve formed this X shape, you can hold the slack from the rest of the string in your middle and ring fingers on the same hand that is wrapped in yarn.
This should leave you with a clear loop and a very open, loose, beginning of a knot. If it doesn’t, try again.
This structure that you’ve ended up with is called a slipknot and is the basis for starting most crochet projects.
This means that the knot should be below the hook.
This is called a yarn over. Hold the yarn tight enough to keep its tension, but loose enough to let it still slide through your fingers while you are crocheting.
If you need to count chains, lay the chain flat. You should see a series of V shapes. Each V is a single chain stitch.
Before you start this new row, you will make a couple of extra chains (usually two, it can vary depending on the size and tightness of your stitches). Chain these extras and then root your next row in the last proper stitch in your chain. It is best for beginners to start with small projects that are worked in flat rows.
With the last loop of your chain on your hook, push the head of the hook into the very first stitch on your chain. This will make two “loops” on the hook. Grab the yarn with your hook, just as if you were chaining normally, and pull it through both loops. This will leave you with one loop on the hook and you’ll be ready to start your next “row”.