Step 2: Software
First, download the actual Wiimote Whiteboard program. For macs, the only one I was able to find was the one at uweschmidt.org. For computers operating on Windows you have a few more options. You can download one off of uweschmidt.org, smoothboard.net, or Johnny Chung Lee's original software at johnnylee.net/projects/wii/. When there, you will have to scroll down to Low-Cost Multi-point Interactive Whiteboards Using the Wiimote and click on Wiimote Whiteboard v0.3. Linux users can download software at uweschmidt.org (again) or at code.google.com/p/linux-whiteboard/.
Second, you will need to download Bluesoleil, if you are using a Bluetooth connector that does not provide already software. Most Macs should have Bluetooth built-in, so Bluesoleil should be unnecessary. Windows users should visit bluesoleil.com/download/index.asp?topic=bluesoleil5x and download the software. If you are using Linux, you should visit bluesoleil.com/download/index.asp?topic=bluesoleillinux then download the appropriate file.