How many articles or video to make to achieve this goal? Beside from article and video marketing what else are the best FREE strategies to achieve 20 visits everyday?
If you want to get visitors to your site then getting good ranking in Google would be the best option, you can get a lot more visitors than 20 if your keywords are in top position in search results. By getting good backlinks you will be able to achieve top ranking for the keywords. And this technique is also free, you do not have to pay anyone, gather some knowledge about seo and then start doing submissions on your own for the website.
Agree with seopro2011.... if your website is optimized for particular keywords and you're ranking at top for those keywords, you can get way more than 20 visitors.... you can get hundreds and thousands if you're ranking at top for a highly competitive term...... And to achieve this goal all you need is the selection of right keywords then their right usage on your page....
Besides backlinks, update your content in a regular interval and send the link on popular social sites that your friends may know about it and get visited.