Three aspects of effective communication

1) Is verbal communications, because then you can help someone understand what you're trying to express if you have previously used body language facial expressions etc. and it didn't work, or they didn't get the correct message.
2)Another one would be using non-verbal communications, but as I said, it could be difficult for someone to understand what you're trying to say. 
3)Listening is also a good one because you want that person to know that you are willing to listen to them, as much as they listen to you. The key to any kind of communication is each person is listening to one another

I hope this helped you out some. :)

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