1. First step is to login to the back end of the website. The login page is located at yourdomain.com/wp-admin, for example mostexposure.com/wp-admin where you enter your user name and password.
2. Once logged in, you will see a dashboard of the website, with options on the left.
3. To edit pages, click on pages item to view all pages 
4. Click on the page you would like to edit, add content, and click on update on the right upper side. You may also create a new page by clicking add new, adding content (works similar to a standard text processor)
5. Depending on configuration of your website, you may have custom post types, such as services or projects. They work similar to pages.