Studies say that approximately 85 percent of all communication is NON-VERBAL. Facial expression, body language, etc. all play an important role in conveying a persons true intentions, even more than the actual words he uses. That is the reason why email and even telephone are inferior ways of communicating. Always try to pick up on hints as to people's true intentions by listening to their intonation and watching them carefully.
When I speak with someone I try to stare them square in the eye. The eyes say SOOO much. It was Emerson who said "The eyes of men converse as much as their tongues, but with the advantage that the ocular dialect needs no dictionary, but is understood the world over." Beautifully put! When I was a child I used to religiously consume Robert Ludlum novels and he would always describe what the persons eyes were saying. Have you ever seen the Lubavitcher Rebbe's eyes? Powerful.
In Torah we also appreciate the power of the eye. Ayin hara is not only a mystical concept but has very practical halachic ramifications [as we see in the beginning of bava basra]. The sefarim are filled with exhortations to look at others with an ayin tova. The prohibition against looking at forbidden images is a biblical one. Moshe was allowed to "see" the Land which was his way of drawing into himself its kedusha. More examples of the centrality of the eyes abound.
Recently I was fortunate enough to meet with a gentleman who has the means to help me achieve my goals. We spoke at length and genuinely enjoyed each others company. He was looking at me a lot. When it came time for him to tell me the news that he was not going to fulfill my request he did something very interesting. He looked away. He didn't want to make eye contact. I feel badly for the poor [not financially though, if you catch my drift] guy. It was clearly uncomfortable for him and by avoiding eye contact he saved himself discomfort. This feeling of discomfort was a display of sensitivity which I appreciate. As far as the negative reply - im yirtze haShem his lucky day will come when he will agree to my offer:-).
So look the person in the eye, be an active listener and really try to understand what the other person is saying. Rare are the people who effectively do this.