If you purl more loosely than you knit (most knitters do), this causes problems when you work the heel of a sock. Learn a way of purling which guarantees nice snug purl stitches - also idea for ribbing and for defining the background for cables.
by Nicko's Kitchen
by Lisa Yang
by ST CRAFTING TV
by TyingItAllTogether
by Hectanooga1 - Crochet, Knitting,
by Ratchadawan Chambers
by oxicleanvideos