Follow this directions to reach the users page [Top Right Icon] -> [Users]
To create new user, Click on the [ New user ] and fill in the Username, Display Name, Password, and Email. Leave the Groups empty if you only want to assign them as standard user. Assign a Quota for them or leave it at [Default Quota] which means [Unlimited] as well. New user created will received the welcome e-mail if you have fill in their e-mail address during user creation.
Great! Now you’re ready to upload your first file!