Know what your desired outcome is. Don't try and sell on the first call. When I was doing this 15 years ago. My goal was to find out if they had a use for my service. I did this by asking questions. Get them talking. If you are talking, you are sounding like every other telemarketer. If they had a use for my service, I would ask to book a call. This depends, of course, on what it is you are selling.