Anyone can contribute to the content on Wikipedia. Marketers have a particular interest in the site since a relevant backlink to one's site from Wikipedia can be very valuable. Naturally then it would make sense for any web marketer to become familiar with Wikipedia and where possible try to leverage it (within the Wikipdia guidelines) as a tool to drive awareness and traffic.
Relevant Wikipedia Guidelines:
As an author or editor it is prohibited to use Wikipedia to promote yourself, your website, or your organization. These are all considered conflicts of interest and are to be avoided.
Be neutral. This is not a place to get on your soap box. It is a play to play the role of non-bias editorial, confirmed, relevant, and valuable informational writer.
While I do not endorse trying to game the system or break the rules I do think you should consider the following:
Setup an Actual Profile
Anyone without a user account can make anonymous edits to Wikipedia pages but those edits are poorly trusted and impossible to followup on or track as the contributor. Setup an actual user account and work hard to build your reputation by following the below tips.
The More You Contribute The More You Are Trusted By Others
If you are a very active member of Wikipedia it shows in your profile. Editors and contributors are very weary of a new user who starts adding links to an external website. Red flag right? On the other hand if you truly work to benefit the website, content, and community everything you do is likely to be taken in good faith.
Legitimately Try to Add Value
If you focus on how you can create more value for others and less on how Wikipedia can create value for you, in the long run the relationship will be very strong and mutually beneficial. Don't look to articles where you would like to have a link back and work hard to find a way to incorporate it. Instead ask yourself if you have content that can truly add to the readers experience and knowledge. If so add it and do it in a way that will add value to the reader.
Take it Slow – Learn The System
Wikipedia is a unique community with it's own coding language, guidelines, and policies. Don't rush in and start making tons of changes, edits, and additions. It won't help you or the readers. Take it slow. Look for small edits you can make to truly improve content in areas where you have expertise or resources. Get familiar with and comfortable with the processes.
Document What You Do
Every time you make an edit to a page you will have the change to explain your changes and add any other relevant change notes to the “talk” page for other editors and contributors to see what you did and why you did it. If you are really adding value to readers you should have no reason not to be transparent and clear about the edits you have made. It will help your reputation and will also make it easier for you to track past contributions you have made.