ERRATA:
ERRATA
Heel Flap on an ODD no if stitches:

Row 1: (WS): Sl 1 p-wise, p to end.
Row 2: (RS): Sl 1 p-wise, #Sl 1, K1; rep from # to end.
Rep the above 2 rows until the heel flap is 23 (23, 25, 27, 27) rows in length from
start of slipped stitch heel pattern, ending on a WS row.

So on row 2, the RS, there are 2 slipped sts at beg of row 2, so you end on a K stitch.

The slipped sts at the beg of rows fold under to form a neat selvedge and aren’t part of the central knitting so you can’t really see them.
Then when you pick up around the edges of a heel flap, you’re picking up along that edge so it hides edge sts even more leaving a ribbed effect on the centre of the Heel Flap.

This contains the PDF Anatomy Of A sock diagram and glossary of some basic terms to help newbies understand sock construction. The design was donated to Médecins Sans Frontières as part of the p/hop project. It is not available from that source now, but I have added it to my Ravelry store for free and hope this inspires you to donate to MSF, my local dog charity Retired Greyhound Charity: Whittingham Kennels which is where I send 100% of my pattern revenue, or another charity of your choice.

This sock is easy enough for a beginner to tackle and you can download an information sheet on the anatomy of a sock from the same page as the pattern.

p/hop is pennies per hour of pleasure, so please feel free to use this pattern, then donate what you think it was worth to you to MSF.

MSF is an independent humanitarian medical aid organisation, committed to providing medical aid wherever it is needed, regardless of race, religion, politics or gender.
They currently work in over 60 countries helping victims of war, natural disasters, disease epidemics and those who simply have no access to even basic healthcare. For more info, please visit www.msf.org.uk
To donate or find out more about p/hop, please visit the p/hop blog at http://www.p-hop.co.uk/