The user profile can be accessed via the My Profile button in the User Menu
It allows to edit the user info (User Id can't be changed by a user)
Note: use 800 x 200 pixels of an image format like gif or jpg, not a pdf )
and the user preferences
Theme: the look of the UI
Date Time settings - This is specifically useful if you are in a different time zone than your server.
Note: for documents the server settings are used.