You can also sign in through the Discovery search results page by clicking the 'Sign In' link on the right-hand side.
Either way, when prompted for a username and password, enter your RRU Login (the same username and password you use for Moodle).
If you've signed in through the Discovery search results page, your first name will appear in the upper right menu. You can now manage your library account and your personal lists by selecting 'My Account' and the appropriate function from the dropdown menu.