Board Thread:Support Requests - Getting Started/@comment-4104343-20140302160757/@comment-4705324-20140302161145

Hi, you can go to Special:UserRights, type in the users' username and change their rights there. You can also accomplish this by going to the users' profile page, clicking Contributions, then clicking User Rights Management.

Be aware, you can generally only promote someone if you're an Admin/Bureaucrat.

Best of luck! :)