Lady Ada has the official instructions for building the MiniPOV on her web site, here
. The MiniPOV is a wonderful little kit using the ATTiny microcontroller to control some LEDs (or whatever other output you can dream up) and it's very hacker-friendly. They even included solder pads for a sensor that the POV design doesn't use just so you could extend it!
for building the Brain Machine say to follow the instructions for the MiniPOV kit except leave off R5, R6, and LEDs 1-4...we'll be replacing the 100Ω resistors with our beefier 1kΩ versions and moving LEDs 1 and 2 off the board onto our glasses. We also are replacing LEDs 3 and 4 with our capacitors and headphones.
The MiniPOV should work just fine with the 4 LEDs missing, so go ahead and test it out (and play with it) after you finish building it and before you program it with the Brain Machine software so that you know it works. Once you're done and you've programmed the Brain Machine software into the chip go ahead and remove the DB9 connector; you won't need it again if you're going to keep this as a Brain Machine and it'll just take up space.