1. Be Simple and Concrete
Are you convincing people with your words? If you talk so formally to your prospects, you don't convince them. Chances re you will only suggest that you are pretentious, that what you're saying is artificial and you're only doing this for the sake of glory to yourself. On the other hand if you use simple and short words, you build a connection between you and your prospects. Your message becomes more vivid and real so they begin to understand and see your point of view.
2. Develop your interest in other people
People love their selves and appreciate those who understand their needs and desires. Take the time to talk with people about their hopes and fears, their beliefs and doubts, their careers and hobbies, their families and loved ones, their experiences and values. You make friends with them. If you develop this quality, what you say will naturally suggest far more to them than the words you use thus improve your convincing power.
3. Explore new fields of knowledge.
If you do this, you'll get your hands on a broader understanding and wider experiences. And while you do this, the talking you do with your prospects will enrich the meaning for them and they will come up with more meaningful images in their vague thoughts. How do you do this? There are lots of opportunities everywhere - books in your home that you seldom read or in the public library, training or study courses in the Internet. Make sure they're reliable information. Also activities like joining a club of your interest and taking part in civic projects lets you meet new people, new experiences and gives you a wider perspective as you impart you knowledge to your prospects.
4. Know What You're Talking About
Get to know them as much as you could if you intend to suggest authority and confidence. Suggest the best about yourself and your message by careful preparation of what you say. So go to your reference, seek out someone who is more knowledgeable in the subject and talk with him, review what you have learned and evaluate yourself. In short, find out whatever you must know to talk with authority and conviction. If you do that, your prospects will think "These guy is smart, he knows his subject well. Ok, I'm convinced. Knowing what he knows, he certainly can't go wrong."