The most important thing you can do to optimize your website is write a lot, relevant and rich text for each page.
A lot of text is good for getting high on search at Google. Then there will be more searches that hit with some of the content on your website. But, at the same time, the text must be relevant in terms of what the page is all about.
When you type text to a page on your website, choose a keyword that clearly expresses the message on the page, and then type the rest of the text around that word. Repeat it in the text here and there, but no more than 5 times.
Write as easy and free as you can. Keep in mind that you write about something you CAN, about your own company and the services you offer. Write as if you're the expert in the field. If it benefit visitors, you'll post useful links to other websites that may provide supplementary information to what you're writing about.
Imagine writing to a special person and typing YOU and YOUR INSTEAD OF MAN and EN. Then you give visitors the feeling that you write directly to them and not generally for everyone.
If it's hard to think of what to write about, check what other websites are doing the same as you, write. It can give you useful tips and help you get to know me.