Here are three videos by Teresa on the single, half double, and double crochet foundation stitches. This gives your work a more flexible edge. It also saves time by doing the chain and first crochet row in one step.
http://www.youtube.com/watch?v=A83tz...5F0D5&index=76
http://www.youtube.com/watch?v=AEBR6...5F0D5&index=75
http://www.youtube.com/watch?v=sCm1m...5F0D5&index=74