When you speak to a salesperson and they're like UM...AH...ER... it doesn't instill a great deal of confidence in the offering. Phone conversations where people are mumbling and stumbling don't create a very positive impression. You should always aim to communicate your ideas and answer any questions that callers have promptly, clearly and effectively. If you speak with confidence, it will always inspire confidence in you and your company. Here are some general rules of thumb to follow for effective communication: