As a great first step, you should check out David Mihm's local ranking factors. Just google it. At the bottom of his post you'll find a sort of checklist. If you take the time to learn that, you'll be way ahead of the game.
In sum, you've got:
1- strong website with schema, reviews, good on-page seo and a landing page for ech location
2- social accounts done, active and full of info
3- structured citations - yellowpages, yelp, etc
4- unstructured citations - youtube, dailymotion, etc.
5- quality link profile
Hope that helps