You can add a new user from the main User management screen by clicking on the [ add a new user ] button. Enter the required new users details and assign a password to the user. Passwords which contain both characters and letters are best however there is no set limitation.
If you add a Login page to you website, your website users will be able to have their passwords emailed to them.
Also remember to select the Groups which are to be assigned to the new user. See the details below for more information about groups.