Make sure there's a bootloader burned on your Arduino board. To check, reset the board. The built-in L LED (which is connected to pin 13) should blink. If it doesn't, there may not be a bootloader on your board.
// pin name: not-mega: mega(1280 and 2560)// slave reset: 10: 53 // MOSI: 11: 51 // MISO: 12: 50 // SCK: 13: 52
avrdude: verifying ...avrdude: verification error, first mismatch at byte 0x1e000 0xff != 0x0davrdude: verification error; content mismatchavrdude: Send: Q   avrdude: Recv: .  avrdude: Recv: . 
Remember that the mega has 2 programmable chips, there are 2 connections, the one near the mega2560 is the one where you upload the bootloader, the other needs the serial+dfu firmware