Connections allow you to view which Ideas are related.
To add, edit or remove Connections, navigate to the Connections menu on the right side bar in your chosen Idea.
Navigate to Ideas, click on the + icon and select the Ideas you would like to connect.
Once you've connected your Idea, you can edit or remove Connections by navigating back to the Connections menu, click the +icon next to Ideas and unselect the relevant Ideas.
Read more about connecting Ideas on the Canvas here.