I disagree.
I've never had an issue at all with safety. I've both bought and sold many things using craiglist - most people are decent and honest. Yes, it is possible to run into a crazy or some idiot who will give you trouble. You can do this in your supermarket parking lot too so should you stop eating?
Yes, DO take precautions...
First of all you can use craigslist built-in email so your personal email never shows up. Still concerned? Set up a separate account with a service like Yahoo. Use a cell phone as they are generally not easily tracable. (though this is likely to change)
To answer your question... selling on craigslist is very easy.
You need to open an account first.
Write an ad like you would write one to sell your time in the classified section of the newspaper. The difference is you have as much room as you need to say what you want. You can add photos if you have them.
Make sure you post the ad in the most appropriate category. You can browse other ads selling similar stuff if you need ideas.