Not sure if this is the correct way to do it, but have been having a go for the past thirty minutes and found this way works.
Use the text box tool from "Wordart" to select an area within each column and expand it to line up with the column edges. [Do one at a time] Now click on the border Icon on the "Draw" tool bar, all you will see are straight borders, but scroll down to the bottom and choose "more" lines. This will open a small window for you to choose border art. Make your selection from there.