There’s a video for knit 1 below on the Glossary page under k-b, doing the purl 1 below would be similar. Insert your needle into the middle of the stitch below the one on your needle and purl it. The st on the needle will drop down a row, it’s supposed to do that.
It should only drop 1 row, down to where you knit the st below the needle and it will be loose. Here’s still pictures of knit 1 below, maybe that will help you visualize it. Also it will look a little better after you knit a few rows of it, it does look like a mest when you’ve just done it.
Ohhhh, thank you for the “still pictures”. It looks like the best instruction so far. I’m not giving up until I figure this out. And like you said, it will look a little better after knitting a few rows. I will post and let you know how I’m doing with this project.