Next time - greeting and presentation. As a welcome gift is best suited neutral "Hello." A common greeting "Good day" may be out of place, if the conversation takes place in the morning or, on the contrary, on the street for a long time it was dark. If you call the customer on behalf of the company, the company's name is announced mandatory. But your own name or the name and patronymic of the call, but not mandatory corporate culture of many companies and prescribes a private performance.
Business etiquette stipulates that the first is to call. However, if the person calling you did not, you can ask him to introduce himself.
If the client requests to the phone of your colleague or boss, but they are not in place, you should not be limited to a brief statement of this fact. Better inform the caller that the employee or supervisor can not come to the phone right now, for any reason (for example, is at the meeting). Then you can tell when an employee is required to place and clarify what information should refer to it. You can also tell that the person call back to the client as soon as available.
If you are not competent in the matter to which you are approached by a customer on the phone, do not say "I do not know" or "It's not up to me." Should either inform the client phone competent in this matter employee or clarify the matter and call back to the client later.
A very important caveat - the end of the conversation on the phone. Perhaps the farewell is no less important than welcome. Whatever there was a conversation with the client (and the situation can be created very different), quiet and friendly "goodbye" at the end of the conversation is necessary. In some companies decided to thank the customer for handling it in this company and looks forward to continuing cooperation (or wish further success to the client).