How to Crochet a Chain Stitch
The chain stitch is where almost every crochet project begins. It forms the foundation row that you'll build your stitches on, and it's also used within patterns for things like turning chains, spaces, and picots.
It's the simplest stitch in crochet, but getting even, consistent chains takes a little practice. The key is keeping your tension steady — not too tight, not too loose.
Getting started
First, make a slip knot and place it on your hook. Hold the hook in your dominant hand and the yarn in the other, with the yarn running over your index finger for tension.

Yarn over (wrap the yarn over your hook from back to front), then pull the yarn through the loop on your hook. That's one chain made.

Repeat: yarn over, pull through. Each chain should be the same size. If your chains are tight and hard to work into later, try going up a hook size for your foundation chain.

When counting chains, don't count the loop on your hook or the slip knot. Each V-shaped link in the chain counts as one.
Tip: If you're a beginner, practice making chains until they feel natural. Good, even tension here makes everything that follows much easier.