HOWEVER, whichever way you do it, you need to have had at least a cup of
coffee first. The initial impulse is to create a grid that matches the
labels. You will quickly discover, though, that what you want is a grid
that matches the live copy area. That means that the top of your virtual
label (hence the top margin on the sheet) has to be about 1/8-inch below
the top of the physical label, and the margins and gutters similarly
need to be padded an eighth of an inch in the appropriate places.