Viewing a note (even if you haven't created one yet for that source) will give you access to the "Create a Note" option.
Click on that link to open a pop-up window where you can type your note and then save it by clicking the "Save" button.
Once you've created a note, viewing it will also give you access to "Print Notes." Clicking this link opens a pop-up window where you need to make a choice to print your notes for "This Source" or "All Sources."
This will open another pop-up window with the print version of your source notes. From here, simply click the "Print" button to send it to your printer.
The right side options menu for the Source Note allows you to "Update this Note," "Delete this Note," and "Create a New Note," as well as listing the date the source note was originally added and when it was last updated.
Selecting "Update this Note" opens a pop-up window where you can make your changes and then save them by clicking the "Save" button.
Selecting "Delete this Note" opens a pop-up window which includes the note and the question "Do you want to delete this Note?" If the answer is yes, click the "Delete" button. This will return you to the Source Notes main page, which is refreshed and no longer includes the deleted note.