Here we’ll show you how you can spy on your competitors. This is going to be a very important part not only with gathering information about what kind of keywords they're paying for but also where they are getting traffic from generally.
Doing a quick Google search with one of the keywords that you want to use will provide you with the competitors who are also bidding for that same keyword. From there you can get their website URL and use spy sites that will help you get more information about them.
There are a lot of sites and companies that offer their service which is basically to help you spy on your competitors and we do recommend using either SpyFu.com or Similarweb.com. Even without subscribing to them, they will be able to tell you where your competitors are getting the majority of their traffic from, the top keywords that they are ranking for, who your other competitors are, etc.