The third step to dissecting a human is looking at the muscles of the abdominal wall, or it can be your first step, or your second; the order's not important. What's important is that you get an "A" in anatomy class.
So, if you want a deeper look at the anatomy of a human, this is the video tutorial for you. You'll see how to reflect the pectoralis major to reveal the pectoralis minor. Then get out your scalpel and perform an incision on the external oblique muscles to see the science of the anterior body wall.
This is very informative for medical students in need of cadaver dissection instructional videos.