Here I will show you how to purl encroachment. I prefer this method because it is the first method I learned how to turn a heel with. It is also sometime referred to as the Sherman Heel/Toe. It takes some getting used to because it is less commonly used. But once you get the idea, it's not bad. For those of you who know how to work short rows with a wrap and turn, feel free to apply that instead. My patterns have not been tested with a wrap and turn, so you will be on your own.
So now that your ready to begin the purl encroachment, you'll notice that you have stitches on the left needle, and stitches on the right needle.
Start by slipping the first stitch on the left-hand needle purlwise onto the right-hand needle.
Next, using your right-hand needle lift the stitch below the next stitch on the left-hand needle and place it onto the left-hand needle. I have used a tapestry needle here for demonstration only. Be sure to use your fingers to prevent it getting too close to the stitch that was already on the needle.
Now slip the previously slipped stitch from the right-hand needle back onto the left-hand needle.
Purl the two stitches together.
Here's what your work will look like once you are done.