This cast-on technique has the same look as a classic bind off edge, but it is a cast-on edge.
To realise it, you will need a crochet hook the same size as the needle you will be using in your project.
Make a loop with a slipknot. Pass the loop on the crochet hook.
With the crochet hook in your right hand, pull the working yarn with your left hand and place the needle above it, near the crochet hook.
With the crochet hook, pass above the needle to catch the working yarn.
With the crochet hook, pass the yarn into the loop on form another loop. You have cast on one stitch.
Replace the working yarn under the needle.
Repeat steps 3 and 4 until you only have one stitch left to cast on.
Pass the loop from the crochet hook to the needle to create the last stitch.
The cast on edge looks like a chain stitch similar to a bind off edge.