First... Log InSimply "log in" to your site by clicking on the login link at the top right of any page of your site.
Now a 'Site Admin Login' field will appear allowing you to log-in with a password. Select your user name from the drop down (there may be more than one if you share admin responsibility with someone else), enter your password, and click on the Log In button.
Once logged in, the 'Site Admin' page loads, displaying a list of the core site editing options.
Beside each option is a small 'plus/minus' symbol. Clicking on this will expand/collapse that section of the admin facilities, displaying the editing options available. Clicking on any of the options displayed will allow you to change those site settings or content.