Depending on the situation, both methods can be very useful. Here are steps for both methods

Go to the Home Panel and scroll until you see the streams section. Then click on the plus button to create a new note series

You will then be prompted to create a series as usual and adding a name and description (optional). There is just an extra step to add the people who you would like to share the note series with.

To turn a note into a shared note series, first find the note on the Home Panel under Streams.

Once that note is selected, click on the Share button in the upper right hand corner of the note.

Add the other users to the note.

Then you should be all good to go! View the note in the Others section of the Home Panel