1. Stumble TONS of pages. Don't just stumble those that do exchanges with you. Hit that stumble button. 2. More reviews to your profile. Just review other people who have similar interests with you (check their last login) and most of the time they will review you back. 3. Interactive stumbleupon pages. include photos (stumbleupon photoblog), videos and you'll become more popular. 4. Join active StumbleUpon group. 5. If you become a sponsor, start your own group.
i may want to continue with more further details, photographic mean stumbleupon photoblog... 6. Put some real cheek pic and see how your fans increasing day by day.