Angular and SEO, how to

Actually, I'm building a site using Angularjs, so, as we now the most calls and rendering process are made using ajax calls and I think this is a problem for doing a good SEO, because crawler/robots cant navigate the whole page.

So, If I using Angularjs, are there any techniques to improve SEO in my site? any pattern ? good practices or something ?

Should I use html5mode ? or # based urls.