Sitcom Writing Exercise

I have to do a beat sheet for a spec script I'm writing. I'm doing a 30 Rock spec and some of my other classmates are doing the same in Sitcom Writing class. When I took a creative writing course a couple years ago, the instructor made us watch old movies and write a screenplay for what we saw in first minute of the film. I started watching the first season of 30 Rock and decided to write down the beat sheet for the first 3 episodes. I found it very helpful and it gave me more confidence with my own beat sheet.