The first step is to add the correct schema metadata to your site. You can learn more about the correct way to do this from Google's 2012 article: [webmasters.googleblog.com...]

It should be noted that adding perfectly coded and accurate metadata does not guarantee that you will see search results with your Rich Snippets, it depends on many other factors including Google's trust of your domain as Robert Charlton mentioned here a few years ago and it seems to be still valid: [webmasterworld.com...]

Google has indicated in several ways that while markup is most likely necessary for the display of rich snippets, it is not sufficient. I'm thinking that authority, trust, and popularity signals are also being factored into the display.