How can I get benifit through Stumble Upon?

Hi All,
Can anyone describe it in detail how we can take more and more benefit from stumbleupon.com( A good social bookmarking site)

 

by submit more to more advertises and bookmarks.

 

Only by directly attracting visitors to your site, their links are not follow so not much for keyword ranking there.

 

Stumble upon is a social bookmarking sites.Through this site we can organize,store,manage and search for bookmarks.It helps you to save your favorite web pages.

 

i used to get lots of traffic from this site but it`s not steady flow, you have to keep on bookmarking sites there everyday