You have to be in the city with the money, open up region view and select the city you want to give the money. In the bar at the bottom you have to press the most right button (I think), it says "gifts"or something.
When you send the money open up the region view and look at the city you are giving the money. You will see a car with a dollar sign (or something that will look like a dollar sign) on top of it. This car will drive to your city and collect the money, afterwards it will drive back to his own city.
Wait until he arrived and you will see a message at the top of the screen. After this is done load the city and the money will be there.
[Edited by m4rk0, 3/13/2013 4:07:41 AM]
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