Welcome back to the Art of Crochet blog!
Popcorns are created by a cluster of stitches that stand proud of the rest of the work. The ones in this square comprise five trebles and to make one you have to take your hook out of the stitch and place it into the top of the first treble in your group. When you reach the end of the round, work a slip stitch into the back of the first popcorn to finish. These popcorns are divided by two chains and these are the loops that the next round is worked on. The square shaping happens in the next round. Here’s a film of making the square.