Developing a website can be quit an easy job with all those WYSIWUG (What You See Is What You Get) website development tools. But one thing they don't do, is making your code optimized for search engines, search engines demands, not only meta data on you website, but also you may want to think about things like content (word density, internal linking etc.), here I will try to give you an brief
overview, of some of the important things to have in mind, when optimizing your website.
Also I can refer to my site where all SEO online and offline tools are free to use and download.

1. Optimize Your Title Tag.
Always important to remember your keywords, also in your titel tag, do never write your company name or something like that, instead use a descriptive text containing as many keywords relevant to your site subject as possible. (Note: keep your title about 60 characters).

2. Creating good content.
Even though your main product is to sell pictures from your website, Google and other search engines can't 'see' them, so you need some descriptive text content, search engines has a very complex way of reading a website for content and to find out what your site is about, so remember to use a lot of good relevant keywords in your text content, (but remember to spread them naturally).

3. What confuses search engines?
Well, this is and has been a very big discussion topic for a long time now, some of the factors that can confuse search engines is JavaScript, using frames on pages, dynamic pages (e.g. asp.net etc). Almost forgot to say that if you are using flash elements, even though there are text in it, search engines can't read it, so not recommended.

4. META tags.
META tags are a way to describe your site for search engines, its text that is not shown on the pages. (Some people claim that Google does nothing with these tags anymore, but we don't know, and I know that other sites uses them, so why not just write them anyway).

META name='description' content='a well optimized short description of your page'>

5. Robots text file
The Robots.txt is a file you have on your site, not for visitors, but for search engines when they look at your site they looks after a robots file, and if it exists it is easier for search engines to index all your sites. You can generate a robot file with this software for free.

6. The thing about images
I mentioned before that search engines can't read images, that’s not completely true, images has an ALT tag, that makes it possible for your to put in a descriptive text to the images, some says that Google sees that, so here is the code:
img src='my_image.jpg' width='50' height='60'
ALT='A descriptive text in here.'

7. Text sizes.
Some people also say that search engines look at text that is emphasized (e.g. h1). So my theory is, if you are doing as I have done for years, just writing text and then set up the visual part in a separate css file, then Google can't se that the text is a header1 or header2 text.
So what to do could be, in your website page, make the text h1 and in a css file define the h1 tag to look different.

H1 { color: blue; font-family: Verdana; font-size: 16px }

8. Remember file naming.
Another thing to look at is your filename, your first page may be named default.html, but if you go to Google and search for something, like 'Free SEO Tools' you can see that Google also looks at sub-directories and filenames, like:
 www.seo.dd-soft.com/SEO-tools-free-download-internal.aspx,
this says more than just download.aspx.

9. Internal linking
Always remember to link your site together, your need search engines to find more then just your front page.

10. Some personal words before you go on making a website.
This last tip is not really a tip, just some words from me personally to you, I have read a lot of literature about SEO, and other marketing techniques, so just do not forget, depending on what your site content is, there may be other ways to market your product, it could even be done cheap or for free, be creative.