There is much mystery surrounding SEO - search engine optimisation, however, there are a number of things that are no mystery and your web designer should do for your website.
1) make sure that every photo is marked with a relevant title and an "alt" title
2) choose "keywords" that match your website and content
3) write your web content with as many of the keywords in your copy as possible
4) make sure you have a "favicon" (a small image of your logo) installed.
5) make sure your web developer has a "robots" file for the search engines to index
6) keep your content updated and fresh