Start by inserting a new Diary macro into your page using either the { }-syntax or the macro browser.
You can now configure the Diary to your needs by changing its macro parameters. If you need help by doing so, or just want to know what each parameter does, please refer to the Macro Parameters documentation.
Save your page and you will see a freshly created Diary without any entries.
Your Diary is now ready to be used! Continue by creating a new Diary entry.