There is no perfect designer that makes no mistakes. Review all your web pages to make sure all the links are working, 404 page, robot.txt, sitemap are all in place, check if you incorporate the title tag for your links etc.
Make sure to incorporate title, keyword and description meta tag into every single page on your site. Use keywords and description that relevant to your page.
This is one of the good spots to place your keyword phrases to increase the searching visibility since most search engines use the meta description as the description in the search results.