Change a password
To do so, select the 'People' button from the vertical toolbar on the left of the screen. Then click to 'View' the profile of the user in question.
From within the profile, click 'Edit details'. This will open a new page.
Within the 'Edit Details' page, click on the 'Credentials' tab and in the password field, type the new password and click the save icon in the bottom right of the page.