2: Once you are inside the classic editor, click into the column you'd like to add a new one before/after.
4 green plus signs will then appear, 2 in the bottom right and 2 in the top left.
You'll notice that there's one inside the existing column, and one on the outside. This is how we differentiate between adding something inside or outside the existing coloumn.
For example, if we wanted to add a column after the one selected we will use the outside plus sign in the bottom right. When you click on this a small green list will appear, choose the '
' option at the bottom.