Addition of web page for SEO

Try to update your content,Search Engines love new contents.
Put articles related to the service you are providing and
invite your visitors to leave comment.

Even you can ask people to publish your article on their website.
In this way you will get quality backlinks and targeted visitors.
Put the clients statement regarding the services you are providing.It will increase the keyword density as well as will show how much you care of your client's.