To find installation directory (MySQL will normally be installed under /usr/local/mysql) :

which mysql

To start the server:

sudo /usr/local/mysql/support-files/mysql.server start

To stop the server:

sudo /usr/local/mysql/support-files/mysql.server stop

To restart the server:

sudo /usr/local/mysql/support-files/mysql.server restart

To login:

mysql -u user_name -p

To add a user:

create user 'user_name'@'%' identified by 'password';

To grant user access:

grant all privileges on database.* to 'user-name'@'%';
flush privileges;

To check server version:

SHOW VARIABLES LIKE "%version%";