1. To begin taking notes in Zotero, choose the item within your library that you want to add a note to by clicking on it in the center pane.  Next, go to the right-hand pane and click the "notes" tab, then click "add."

2.  Type in the text editor that opens up.  Your note will be automatically saved as an attachment beneath the item (article, book, etc...) as you are typing.  Note:  you can edit the note in a separate window by clicking on the 3 dots in the upper right corner.  Doing so provides you with more screen flexibility while taking notes.

3. The text editor also has rich text features. This means you can highlight meaningful notes, make lists, or use other editing tools to help make your notes as meaningful as possible for you. In this example, I highlighted the key definition so I could easily find it again. I also used a different text color to signal to myself when I am brainstorming my own thoughts vs. taking quotes directly from the text.

4.  If you want to copy text from a website, such as the page on which a journal article is displayed, just select the text you want to copy on the website then right click (or on a Mac, control click) and select "Add Selection to Zotero Note" from the menu.  The selected text will automatically be copied into your current Zotero note.

5.  You can add as many notes as you like to an item.  You can also search for notes by using the search box on the Zotero toolbar.  Sometimes it can be helpful to see all of the notes in a collection at once.  To see all of your notes, place your cursor in the center pane then hold the shift and + keys at the same time.  All of your items will be expanded so that you can see the attachments beneath each item.