Digg and Del.icio.us are networking sites that work by giving you huge amounts of traffic over a very short period of time. If you make the front page here you can get a sudden boost to your statistics. StumbleUpon works in a different way and will give you a steady stream of visitors if you use it properly. (More information on using Digg is available here.)
First of all you need to become a member and download the tool bar which holds all the controls you will need to use this social network.
Stumbleupon has no front page. The tool bar allows you to rate website that you visit (including your own) and you simply click on the "thumbs up" or "thumbs down" buttons according to your preferences. You select preferences and click on the "Stumble" button to see sites that might be of interest to you. This tool bar is simple to install and it tracks what you have seen, and what you prefer, so that you get to see what you want when you "Stumble". You don't have to provide any information that you don't want to when you install this tool bar.
This is the way to add a site to Stumbleupon. Simply click on the "thumbs up".
If you are trying to increase traffic to your article, blog or website, you need to improve on this. The more sites you visit and give the thumbs up to, the more sites of this type you will be given when you click on the "stumble" button and the more often your own relevant sites/articles will be given to other people. This will increase the number of visitors you have.
You can add you own sites too by simply clicking on the "I like It" button on the tool bar, but over use of this might get you barred from the site, so take care.
Add lots of friends because your friends will be given your latest website/additions when they "Stumble" and friends are more likely to give you the "thumbs up".
When you add new websites and pages try to add them to the right category so that the "Stumblers" seeing them are more likely to be interested in them and so more likely to give them a "thumbs up". For example, if you write about computers and you add your new article to the sports section, you are very likely to get a lot of "thumbs down" reactions because the people seeing your article or blog, are expecting sports orientated pages to come up.
Use tags and keywords and keep these as relevant as you can so that when someone "Stumbles" your pages, they get what they expect to see. More information on keywords and tags is available in here.