In order to add a daily note, click on the Bed View header on a selected day. You will see a Daily Notes window where you can see already created notes and add new ones:
When a note is created, you will see it this way on Bed View:
All notes will be visible when you move the cursor over the note icon or when you click on it to open the window. It is possible to add more than one note, you can do that in Daily Notes window.