What advice would you give to someone to help them telephone successfully?

What advice would you give to someone to help them telephone successfully?
To start with, in our fast-moving world telephone calls are very popular. People use their phones every day at work, at home, on weekdays and on weekends. Sometimes we have to talk to strangers or especially to foreigners on the phone. What should be done to make such a conversation more effective and less nervous?
First of all, you need to prepare before your phone conversation. What I mean, is that if you are talking to a person for whom English is a foreign language too, try to speak slowly and clearly and be patient if a person leaves gaps while searching for words. Do not interrupt him or her. Secondly, do not forget that every country has its own codes of etiquette. For example, in some countries, people can interrupt each other, while discussing important topics. For them conversation is a form of entertainment. Whereas in other countries the ability to listen is essential and if you break someone’s speech you will seem impolite or even rude. Remember that different cultures have different rules of etiquette. So, before a phone conversation try to study some of them. Thirdly, you need to choose the right level in formality. Do not be too informal not to seem rude and you should also not to be too formal, because it can make a person feel uncomfortable. Try to find a golden mean. Fourth, if you do not understand something, it is better to ask to clarify it than to pretend you understand something that you didn't.
To sum up, very often people do not notice if a person they talk to does not respect rules of etiquette or is not prepared enough for a conversation, but they will immediately feel if a person is not polite and they do not sense goodwill.

How to improve telephoning skills in English.
To start with, nowadays English is the most widely spoken foreign language in the world. That is why it is important to learn how to speak this language not only face to face, but also on the phone, because there you can find some difficulties.