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Choose your strategy

If you're a beginner, you should start with penpals and text chat.
Penpals are for everyone because you can take your time writing email.
If you're intermediate, you should practice using voice chat.
If your level is above intermediate, you're perfect for voice chat!
If you're not sure about your level, you could try talking with someone and test yourself.

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Judge your level

You are at an intermediate level if you:
- know the basics of the language, (basic vocabulary, grammar and pronunciation)
‏ - can carry on a simple conversation - even if your sentences are not always grammatically correct, and even if you sometimes don't catch a word or a phrase can get the gist of what is being said in everyday conversations with or by native speakers
- understand enough of what native speakers of the language say when they speak slowly.

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Take charge of your own learning

Ask for explanations immediately when something is not clear.
Feel free to ask your partner to repeat, explain or translate when you don't understand something.
Ask your partner to slow down if they speak too fast.
Make an effort to speak out, even if you're shy.

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Be sensitive to your partners' needs

When speaking in your own language, keep in mind that you're doing this so your partner can practice, encourage him to participate, and make sure he can follow the conversation.
Explain, repeat, write down or translate when necessary, and slow down if your partner ask you to.
If someone says a word that you don't understand (because of poor pronunciation, for example), just ask him to write it in the text box, then say it for him.
Encourage those who are too shy to speak.

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Giving corrections

Strive for communication, not correction.
Our goal is to communicate and be understood.
Don't correct grammar all the time, and especially do not interrupt someone in the middle of a sentence to correct him or her - too much correction interferes with the conversation and can frustrate and block speakers.
Do however clear up errors that interfere with understanding.
The best way to correct is to just repeat the word or phrase the way you would say it, even if it is not proper language.

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Be considerate

Speak loudly and clearly - think of when you give an address over the phone.
Give everyone a chance to speak - don't monopolize the conversation.
Develop a listening attitude.
Allow others their point of view - you can comment, but don't judge.

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Organize your time

A way to organize the exchange lesson could be to use half the time speaking in the language you're practicing, and half the time in your own language.
A more effective way could be speaking all the time in the language you are practicing, so everyone speaks in the language that they're practicing.

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Practice regularly

It's like physical exercise: a little here and there is fun, but not very effective.
You need regular, quality practice to see results.

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Please do not skip the warm-ups

They may not seem very challenging and maybe a little silly but those games are designed to help everyone relax and be comfortable in order to benefit from the practice.
A good way to warm-up could be to practice past and future tense talking about what you did that day or what you plan to do tomorrow.

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Relax and enjoy!

Credits:
This text is adapted from http://www.mylanguageexchange.com/HowTo.asp