Blue Painter's Tape
I bought my cork and picture hanging strips from WalMart. The cork comes with the little square stickies that you see in the horrible picture below but, after testing one of the stickies on the wall, found out that they're not easy to remove from the paint so I wouldn't recommend using those to hang your boards. I had the picture strips, washi and painter's tape on hand.
First, put a piece of washi tape across the cork from corner to corner. That marks your center point. Then, put a piece of the painter's tape directly next to the original strip of washi. While the painter's tape is in place, put a strip of washi on the other side of the painter's tape. The painter's tape acts as a ruler of sorts to space out your stripes. Continue this process until you reach the end.
I also made some cute flower push pins to hang things on my board so I'll have that simple tutorial up soon