Here are videos showing the 7 exercises, along with some tips for avoiding potential damage (don't slide down after the wall sit, for example, push up, so you don't damage your knees):
http://lifehacker.com/these-12-videos-show-the-proper-form-f...
http://lifehacker.com/these-12-videos-show-the-proper-form-f...
Your toes need to be pointed out 30 degrees and knees spread apart, crotch opened as far as possible.
You'll find a lot of wrong YouTube videos. It's a minefield of fitness non-experts trying to make a profit. Follow Starting Strength form recommendations and make sure the videos you're watching follow them approximately.