Keyword research is one of the most misunderstood parts of the SEO process. Many new online marketers get the impression that it’s a one-time event. You do your keyword research and there’s your list, never to be thought of again. Nothing could be further from the truth.
In fact, what you should do is revisit your keyword list periodically. Not every day, but at least once every six months. If you are marketing in an industry that sees a lot of flux and change, then you should revisit your keyword list more often.
The purpose of keyword research is see what people are searching for within a specific niche. That doesn’t mean you want to chase the most searched for keywords. If a popular keyword phrase doesn’t suit your business, then discard it. But remember that search queries change over time. What people searched for last year to find information on a certain topic might not be the same thing they search for next year. The best online marketers keep an eye on current search trends.
As far as search trends go, you should take a look at them once a month at a minimum. Measure the trends on the popular search engines as well as the popular social media sites. If something catches your eye as a trending topic in your niche, write a blog post about it. Ride the wave.