1. Go to here to get MySQL for Mac: http://dev.mysql.com/downloads/mysql/
2. Download the 32 bit .dmg archive. Click 'No thanks, just take me to the downloads!'
3. Run the archive and installer. (i.e. the mysql-5.x.xx-osx10.6-x86.pkg)
4. Set your root password by opening terminal and entering:
sudo ./mysqladmin -u root password mysecretpassword
(I couldn't figure out the default password, nor was I asked to enter one during the installation)
5. Login and test it.
./mysql -u root -p
6. Open the dmg file you downloaded in step #2. Run the MySQLStartupItem.pkg.
7. Download MySQLWorkbench from http://dev.mysql.com/downloads/workbench/5.2.html if you need a GUI.