Practice, practice, practice!
Despite its namesake, you’ll want to warm up before jumping into a cold call.
Source: Business writer Tricia Dempsey
Find a friend who’s willing to constructively criticize and guide you through your script. Don’t have anyone to practice with? Record and critique yourself!
Additionally, keep track of the pitches that work well and the ones that don’t. This will allow you to spot patterns and will make it easier to adjust future pitches.