timeout communicating with programmer

Using Arduino Installation & Troubleshooting
#1

Hi,
I bought a MEGA 2560 R3 the other day and as a way of getting my feet wet i was supposed to upload an example sketch from the Arduino software it says:

avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_getsync(): timeout communicating with programmer

I am on a Macbook Pro, using OS X 10.9.4.

I see from this forum and many others that many people have had this problem. Whatever advice is given to me, it is much appreciated but I should point that I have zero experience with Arduinos, so please make sure to keep the steps somewhat simple if possible.

Thanks very much.

#2

Did you read the troubleshooting guide?

http://www.arduino.cc/en/Guide/Troubleshooting#upload

A number of people have reported that changing their USB cable fixed the problem.

#3