A user can choose between 3 different options to set as their opening page when they log in (Cashregister, Calendar, or the Dashboard).

To set your own User home page, go to your User preferences by clicking in the upper right hand corner and clicking on your name. Click anywhere on the User settings page to edit. Enter in your password to verify you are able to edit your own account.
Then scroll down and click the "Select a page" button to view the options. Once you set the option, you can log out and then log back in to make sure your Home page has been set.