First I don't have either a Mega or a MPU6050 to hand so I can't be 100% but A quick Google search says that its an I2C device, so you should be able to just use the I2C pins on the Mega (20 (SDA) 21 (SCL)) and some of the example code on http://playground.arduino.cc/Main/MPU-6050#info
NOTE: Depending on the breakout board you are using you might have to level shift the I2C pins to 3.3 volts.
