You mentioned: "many times clients have already done this work.  Ask them for copies of their market research reports when you start a project.  It will save you a ton of time and effort!"  We do this with most of our clients, like you said we have found that around 75% of the have some kind of Market research done, that saves you a lot of time and helps setting up the right SEO Strategy. 
Hey Brian, I have landed in this blog while visiting via blog land. I must appreciate your effort to put up such informative content. As being an Internet Marketing Consultant, I would like to add few thought of my own with your valuable content. There are many people who wants HUGE number of traffic with no time at all. But as per my experience, SEO has become SLOW-BUT-STEADY process in the recent times. After so many algorithm updates of Google, I think if we will do any wrong things with the websites, that should be paid off. So without taking any risk, we need to work ethically so that slowly the website will get the authority and grab the targeting traffic. What do you think mate? I am eagerly looking forward to your reply and love to see more valuable write-ups from your side. Why don’t you write about some important points about Hummingbird Updates of Google. It will be a good read. Right brother? 🙂
Google uses a hyperlink based algorithm (known as ‘PageRank’) to calculate the popularity and authority of a page, and while Google is far more sophisticated today, this is still a fundamental signal in ranking. SEO can therefore also include activity to help improve the number and quality of ‘inbound links’ to a website, from other websites. This activity has historically been known as ‘link building’, but is really just marketing a brand with an emphasis online, through content or digital PR for example.
You have complied an amazing list here…I am learning a lot about Seo everyday, the more I lean the more I realize, how much it is changing on daily basis. Google is getting smarter with its algorithms and the techniques that once were considered gold are not good enough anymore. So, I agree to all these points you have shared and really appreciate your efforts on this post. Thanks
Users will occasionally come to a page that doesn't exist on your site, either by following a broken link or typing in the wrong URL. Having a custom 404 page30 that kindly guides users back to a working page on your site can greatly improve a user's experience. Your 404 page should probably have a link back to your root page and could also provide links to popular or related content on your site. You can use Google Search Console to find the sources of URLs causing "not found" errors31.

If the user intent is split between more users who are researching for academic purposes and users who are researching to make a purchase, Google will rank webpages that are informational than transactional. No matter how many links you amass to your page, if the user intent of your page is unpopular then you will never crack the top five of any search engine.
Simply put, search engine optimization (SEO) is the process of optimizing the content, technical set-up, and reach of your website so that your pages appear at the top of a search engine result for a specific set of keyword terms. Ultimately, the goal is to attract visitors to your website when they search for products, services, or information related to your business.
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