Make sure that your phone has a display and that the function to show the duration of each phone call is activated. When you keep your eyes on the timer from time to time you will first wonder how much time you sometimes spend on a call and then use it to discipline yourself.
Although phone costs significantly decreased and will more or less disappear in future this is also a way to manage your communication costs - especially if you make a lot of overseas calls.
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This is a great article, but unfortunately my phone does not have a timer.
So what I have started to use at work is an egg timer. I find that because I am monitoring the time of my phone call I actually become much more aware of the time that I spend on the phone.
Another good way to spend less time on the phone is to make your phone calls standing up.
Thanks for the article
Kell