Writing a sitcom: Where to start

You've decided to write a sitcom? Good for you.

Perhaps you are a professional who's been writing in a different genre for a long time. Perhaps you are an enthusiastic amateur who wants to move beyond writing as a hobby. Perhaps you are entirely new.

One of the initial issues you will face is dreaming up an idea for an original sitcom to write.

There are essentially two approaches you can take to this. One is to try and devise a sitcom based in a scenario. The other is to generate a central character or characters that you then build...