Google is your friend, you will find multiple links to YouTube, frugal.families.com, ehow.com,wikihow, etc. Basically you back up your work area with a darning egg (or equivalent hard, curved object to mimic the desired shape of the repair) and create a network of woven strands across it, anchoring them into the solid area surrounding the damage. I remember my grandmother repairing all manner of clothing while she took her mandatory afternoon "rest break," and my mother repairs her hand-knit socks as well.