First download the right MySQL installer .pkg from the MySQL site. This should mount as a disk image on the desktop. Double click and install the package, then double click the Mysql.prefpane and it will offer you two choices : Install for all users or install for current user. Select which you want then load up the terminal.

In the terminal type the following :

cd /usr/local/mysql
sudo chown -R mysql data/
sudo echo
sudo ./bin/mysqld_safe &

At this stage you close the terminal window and open a new one and do the following :

/usr/local/mysql/bin/mysql test

You should get some thing like “Welcome to MySQL” type thing at this point, that means it’s all fine and working. Type q to quit the montior. Next we need to setup the root password for MySQL by doing the following:

/usr/local/mysql/bin/mysqladmin -u root password thepasswordyouwant

Thats it you should be done, to control the system and add users check the documentation or you can use things like the MySQL administrator app or phpMyAdmin, there is plenty of bits out there.

Tested using Mac OS X 10.4.5 and MySQL 5.0.18