If you want to find the best keyword opportunities for PPC and paid ads, there's a lot you need to do to make your campaign effective. You have to create everything from the landing page and ad to the campaign framework. A/B testing is also required for many aspects of the landing page and ad.
At the beginning of your campaign, you should try to brainstorm ideas for keywords. Try to develop a long list to exhaust as many opportunities as possible, including generic, related, brand, and competitor terms.
Select local search keywords that target individuals in the areas you serve. This is incredibly helpful for brick and mortar businesses, making it easier for potential customers to find them.
Once you have a long list of keywords to bid on, you should take the time to narrow it down as much as possible. Eliminate any mildly irrelevant keywords that might be too broad to give you the ideal results, and highlight the specific ones that you feel may prove effective in your campaign. You should also mark negative keywords that you don't want to rank for in Google.
Next, it's important to consider the level of competition that each of your chosen keywords has behind it, and figure out the overall cost to prevent any surprises.
There are plenty of tools available to use to help determine which keywords are ideal, including Google's Keyword Planner, Google Insights, and HubSpot's Keyword Grader. The Clickx dashboard is also great for analyzing your rankings and can provide further ideas.