I simply look at where the file is going to go and choose a tab that won't be directly behind another. It doesn't make a perfect alternating pattern, but in the long run my files look pretty evenly spaced. In the back of my mind, I always wish for perfectly alternating files, but I realize that it is impossible. Even if you could do it, the files would still look uneven because each file is a different thickness. And what would you do if you had to remove files in the future? Its selfdefeating. My concession to my need for perfectness is to use a labeller to make tab labels. It doesn't really take much more time than hand writing, and it makes my files look pretty. Just make sure that you have spare cartridges, so that you don't have an excuse not to file .