The basic idea is this: You sign your website (or just your topsite) up for another topsite. Then you register their topsite on yours. Once you send them a few hits, your rank on their topsite will rise. People will click the link from the other topsite to visit yours. Each hit from their topsite will cause it's rank on yours to rise. This is where it gets good; as people click from your topsite to theirs, your rank there gets higher and more people will click back to you, which causes their rank to increase on your topsite, so even more people click from you to the other topsite. It causes a loopback effect and your visitors will increase dramatically!

This should only be done sparingly, however! People will react badly to a topsite that links mostly to other topsites. It can become a bit of an endless loop if it is overdone, and they never see any real content from any of your links. You wouldn't want them to leave your topsite with a bad taste in their mouth, never to return again.

It is best limit yourself to 2-3 other topsites at the most. Make sure you only do it with the best topsites you can find to maximize the effect. You should also consider doing this with other non-TopsiteStation toplists, perhaps only with non-TS toplists. This would bring even more unique hits "into the loop".