Is there a way to distribute ruler guides evenly between margins to divide up your page? You could go to Layout > Create Guides. But you could also just drag ruler guides onto your page, snapping one to each margin, plus a guide for each division in between the margins.
To distribute the guides evenly, marquee across guides with your Selection tool (making sure not to select any other object) and in the Align palette (Window > Objects & Layout > Align), click a vertical or horizontal Distribute button depending on the orientation of the guides to be distributed. Wow! Now that’s fast, and with no math and no calculator.
Tip provided by Jeff Witchel, Certified Adobe® Training Provider.