This is a fun and easy way to change things up a bit.
I was reminded today how much I love the look of hdc between the stitches... Just how pretty of a piece it makes.
and here it is again.
This stitch is so simple and quick. You just want to insert your hook in a little different location than you normally do when making a stitch and then work your stitch like normal.
Normally when crocheting you insert your hook and catch the two loops on the top of the stitch. The front loop and the back loop. When making a hdc or taller stitch, you will have a bar on the back of the stitch right below your front loop and back loop. Often this is called the back bar of the stitch (I have also seen it referred to as horizontal bar or something similar). So when you are working between the stitches you want to insert your hook below that bar and catch all three loops. (Front loop, back loop, and back bar.)
In the video below I go into greater detail.