There are some people who show their ability of communicating after being given birth. However, there are also some have to learn to communicate well. And the truth is that anyone can build rapport, from with a clients, a boss, in a job interview, or with a manager or employee to when chatting up a stranger, in a relationship, or with anyone really. And to be a good communicator, you should prepare some knowledge and practise it.
Basically, there are some simple guidelines that you can follow to establish rapport. These guidelines can get anyone to feel like you are on their side and see you as someone they can warm to. The two simplest involve body language and voice.
Let us say you are sitting with someone and wish to establish rapport. Notice what they are doing and do something similar. For example, if they are making circles with their hands in the air, maybe you can make circles with a foot. If they are sitting cross-legged, maybe you can sit cross-legged or simply cross your feet. If they are crossing their arms, a sure sign of defensiveness, maybe you can cross your hands across your lap.
If you are talking on the phone, your whole voice sounds better when you are smiling. Even if you have to force a smile, it is amazing how well this works. The only exception is when it is inappropriate to smile, such as when someone tells you of a loss. If your client is shouting and you are whispering, or vice versa, that also needs to be balanced. Of course, we must never shout at anyone! If a person is talking very fast, try to match their speed; and then you can slow down gradually. And they will follow. If a person is talking very slowly, you too can talk slowly.
So simply put, mimic the person slightly without mimicking them too much. Remember how as children someone mimicked us and it was really annoying or embarrassing? So we do not mimic completely but just enough to establish rapport. Practice these simple guidelines and see how you feel.
If you would like to take things further, you may wish to do a course in NLP. NLP is short for Neuro-Linguistic Programming and teaches many strategies for success. You can also buy an introductory NLP book or NLP DVDs. You may be pleasantly surprised how much you can benefit.