5.You should have 3 loops on your hook, yarn over.
6.Pull through all 3
Food For Thought:
The half double crochet stitch (hdc) is made by bringing the last loop through 3 loops on the hook, rather than only 2 loops as in single or double crochets. As a result, when working back and forth to create a piece of fabric, natural ridges will appear from that extra loop. However, when working in the round, as in making a hat, you do not get the same ridged look as you do when you turn the piece at the end of each row. This can be an interesting design element.