How do I word my resume properly? It seems repetitive...

I have been a freelance web designer for longer than the past ten years. Now that I want to try to enter the industry and earn a steady salary, how should I tailor my resume?

I find that for each job/position I used the same skillset. This causes each job entry to be the same… how can I differentiate them?

i.e.:

Web Developer, X Company City, State 2006–2007
Produced graphic sketches and design layouts for online content. Determined size and arrangement of illustrative material and copy, selected style and size of type, and arranged layout based upon available space, knowledge of layout principles, and aesthetic design concepts. Designed and constructed commercial websites and incorporated graphic user interfaces and other techniques.

Web Developer, Y Company City, State 2005–2007
Produced graphic sketches and design layouts for online content. Designed and constructed commercial and individual websites and incorporated graphic user interfaces and other techniques.

Web Developer, Z University City, State 1999–2005
Designed and constructed collegiate websites and incorporated graphic user interface features and other techniques. Maintained and provided ongoing design of the website as well as seasonal content. Led and directed the work of others.

Web Developer, Self-Employed City, State 1997–2008
Produced graphic sketches, designs, and copy layouts for online content, as well as print. Determined size and arrangement of illustrative material and copy, selected style and size of type, and arranged layout based upon available space, knowledge of layout principles, and aesthetic design concepts. Designed and constructed individual websites and incorporated graphic user interfaces and other techniques.

This is my resume, with the companies and locations generalized. What am I doing wrong? How can I improve?

I already will be including a portfolio with this resume, as well as a cover letter. This question is specifically asking what should be done with my wording – to make it less repetitive.