Knit Kit: How to Purl Stitch
The purl stitch is the second stitch you learn when learning how to knit. It's my personal fave as it looks like little waves. A purl is really just a knit stitch backwards. So if you make a knit stitch you'll see purls are on the back of knit stitches and knits are on backs of purls!
Here's a simple slowed down video showing you how to purl. You'll see I put the tip of the needle through the front of the loop with the yarn that's attached to the ball in front as well.
If you remember that a purl is everything in the front, and knit is in all at the back you'll know if you're doing the right stitch.