2 keywords trouble

Hi there.... I'm still exploring SEO world and I would like to have some ideas from you on this issue.

My pages are about photos/images/pictures of AAA or BBB.

Let say that I want optimize for the keyword AAA (1) and for the keyword BBB (2) and NOT so much for something like pictures of AAA or pictures of BBB or photo of AAA or photo of BBB or similar key phrases as they have not a good popularity in monthly numbers of searches but the single words itself AAA and BBB have.

So... I want FOCUS all the maximum optimization as possible on the words AAA (1) and BBB (2) ITSELF much more then phrases combinations above…

What can I do exactly about?

Title ?
meta Description ?
meta Keywords ?

The search engine looks at the weight of the word that the word has on the page. That means that the search engine looks at how important that word is in the page and puts that keyword at the top of the list of keywords. Meaning your page would more likely come up at the top rather than at the bottom.

The way the importance of the word is determined is how often that keyword has being used in important places, such as the title, header tags, bold or any other emphasize on the keyword, and generally how many times it has being used in the body of the text. Having the keywords AAA or BBB as the value to the image attribute 'alt' is helpful too.

This is just a theory of mine (I've never really looked into it), but the name of the image (name.png) also might have an impact on that importance meter. So having AAA.jpg or BBB.jpg would also help you out (I think).

This is what I got about SEO when I was learning some SEO. This is just the basic side of it... there are backlinks that would give you a lot of help to the page and some other things.

Just to clarify better make some example....

I have 'Milan' (AAA keyword)
I have 'Lombardia' (BBB keyword)

I can make all keyphrase possible using other common words like images, photos, photography, pictures and so on...

My goal anyway is to rank for... AAA or BBB or both but not really care to rank on keyphrase as they have not so much a popularity search index.

Ideas???