Inserting an afterthought heel
Usually your pattern will tell you where to join your yarn. For my example, I am going to join between the two 10-stitch needles.
Again, we need to pick up two stitches in the gap.
Now that everything is set up, it's time to put a little thought into our afterthought heel.
When you are shaping an afterthought heel you typically use paired decreases. This simply means you decrease two stitches on each side of the heel.
There are a variety of styles of paired decreases that you can choose from. Today let's use a banded, paired decrease.
For a longer heel, make paired decreases every other round for the desired length.
I prefer to work the paired decreases every other round until half of my stitches remain and then work the paired decreases every round until 8-12 stitches remain.
Finally, use the Kitchener Stitch to join the bottom of the heel.
Here's both the left and right sides of my afterthought heel.
Happy sock knitting!