Homemade Atmega328P-AU programmer

take the 10-pin connector on the end.. stick header pins/jumpers to:

1 - VCC
2 - MOSI
3 - GND
6 - RESET
8 - SCK
10 - MISO

and connect to my Arduino board to: (respectively matching above)

+5v
D11
GND
RSET
D13
D12

I think you'll need pin 10 instead of reset? This was mentioned early in this thread