If you already downloaded Diem, checked your server requirements and created an empty project, what's next ?
Create a first website with this simple tutorial.
Download full projects built with Diem. Study other's code may be the right way to learn how Diem works and what you can do with it.
If you don't know symfony and Doctrine, the following links may help you
Questions and Feedback
If you need support or have a technical question, you can post to the google group.