Overview

This Instructable is the simple version of the MaKey MaKey Monome, an electronic music instrument designed to be easy for kids and beginners to reproduce (and iterate upon!). For more information, feel free to check out my website.

Materials

MaKey MaKey
17 alligator clips (8 columns, 8 rows, and 1 to connect to ground)
copper tape
non-conductive clear tape (Scotch)

Get the Code

Install the Arduino IDE if you haven't already.
Install the Sparkfun MaKey MaKey addon in order to upload Arduino code to the MaKey MaKey board.
Download MaKey MaKey code from GitHub (or simply edit the Settings.h file using the pin mapping below)
Open simple_makey_makey_monome.ino in Arduino, select "MaKey MaKey" as the board, and upload new code to the MaKey MaKey.
Open Scratch monome program.

Step 1: Create the Grid

Copper Tape Grid

Lay 8 columns of copper tape.
Use clear tape to cover the columns of copper everywhere the rows will cross the columns. It's important that the rows and columns of copper tape don't touch (they're insulated/separated by clear tape).
Use alligator clips to connect the columns of copper tape (labeled 1 through 8).
Connect alligator clips to the rows of copper tape (labeled a through h).

Alternative: Conductive Paint Grid

It's possible to build this instrument using conductive paint following the same process. Make sure, however, that when the columns cross the rows, the paint from each doesn't touch.

Paint the columns with conductive paint (Bare Conductive is good).
Cover the columns with clear nail polish everywhere they will cross with rows (to make sure columns and rows are separated by a insulating/non-conductive layer)
Paint the rows.

Feel free to experiment with button design by painting different patterns!