Prepare pans: Using the side of 8 in. square pan as a guide, cut 9 dividers of heavy, clean paperboard each approximately 8 x 2 in. (the back of a tablet of paper works well). Each pan will use 3 dividers for four sections of batter, check to be certain pieces fit snugly in pans. Grease and flour pans, then position dividers equally across pan, tape to fit securely. Note: Dividers and tape will be removed before baking. Set pans aside. Preheat oven to 350°F, and separately prepare cake mixes according to package directions.