How use ATiny45/20PU or ATiny85/20PU with Arduino as ISP?

How use ATiny45/20PU or ATiny85/20PU with Arduino as ISP?

I came across this awesome Arduino board as ATtiny programmer article from the high-low tech group at MIT and thought I'd give it a shot.
I've setup all the components as the diagram suggests but ran into issues uploading the code:
         Using Port                    : /dev/tty.usbmodem641
         Using Programmer              : stk500v1
         Overriding Baud Rate          : 9600
avrdude: Send: 0 [30]   [20]
avrdude: Send: 0 [30]   [20]
avrdude: Send: 0 [30]   [20]
avrdude: ser_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding

avrdude done.  Thank you.
I had a look at a few answers like this and this, tried both but no luck.
Running avrdude -P /dev/tty.usbmodem641 -b 19200 -c avrisp -p m328p –n in Terminal results in: avrdude: stk500_recv(): programmer is not responding
Any hints on what I might be missing/doing wrong ? Thanks!