[Exercise 5: Take A Walk]

help!!!!!!!

I've done this thing ten different times with five different characters. The Paste Mirrored Function doesn't do anything. The book says it should take an hour to do this. I've been doing this for four days. Someone pleasse tell me where I can talk to asome one in person and get some help with this thing because the video tutorial and the manual don't help. I've done everything they say over and over just like they say, but all i can do is add keyframes by posing and cycle through them. I can't do the part where you add the mirrored keyframes. Please help!!!!!!!! I am so frustrated.