Hey, Matt! Thank you for your sharing, and I learned much from it, but I still have a question. We began to do SEO work for our site 2 years ago, and our organic traffic grew 5 times ( from 8K to 40K every day). But two years later, it is very difficult to get it grow more, even it drop to 3.2K every day. So can you give me any advice to make our site's traffic grow again? Thank you in advance!
As you build out your marketing strategy, it’s important to consider how you can best address all of your business goals through a combination of organic and paid marketing tactics. Some goals will lend themselves to one or the other. Other goals may require a combination of the two working hand-in-hand. Either way, both types of marketing will help you achieve your business goals in with impact and efficiency.

Your site is GOOD! Well-written, informative, authentic. You live it; you write it. You are spot-on for what your "typical reader" needs/wants. That authenticity makes a difference. Yes, I've surfed around other low-carb diet sites, but I feel like they are just "spouting" at me. Your posts are written as if we're sisters or best friends and you're talking WITH me.

Let’s say, for example, that you run a construction business that helps with home repairs after natural disasters and you want to advertise that service. The official term for the service is “fire restoration,” but keyword research may indicate that customers in your area search instead for “fire repair” or “repair fire damage to house.” By not optimizing for these two keywords, you’ll lose out on a lot of traffic and potential customers, even if “fire restoration” is technically more correct.
As an Internet marketing strategy, SEO considers how search engines work, the computer programmed algorithms which dictate search engine behavior, what people search for, the actual search terms or keywords typed into search engines, and which search engines are preferred by their targeted audience. Optimizing a website may involve editing its content, adding content, doing HTML, and associated coding to both increase its relevance to specific keywords and to remove barriers to the indexing activities of search engines. Promoting a site to increase the number of backlinks, or inbound links, is another SEO tactic. By May 2015, mobile search had surpassed desktop search.[3] In 2015, it was reported that Google is developing and promoting mobile search as a key feature within future products. In response, many brands are beginning to take a different approach to their Internet marketing strategies.[4]

Billions of people search the web every day. Search engine marketing (SEM for short) is how you can get your ads in front of these future customers where it counts: in premium spots on the first page of search results. You set your own budget and are charged only when your ad is clicked. This makes SEM an affordable way to reach more customers for businesses of all sizes — including yours.
Use images. Images are vital for breaking up the monotony of a string of paragraphs. You also need to use a featured image ito make your content stand out in a list. This is like erecting a virtual billboard. If you don't include one, people won’t realize that your content exists. Think about how these images will look in thumbnail form, as that’s what will appear on your social media feed.
The leading search engines, such as Google, Bing and Yahoo!, use crawlers to find pages for their algorithmic search results. Pages that are linked from other search engine indexed pages do not need to be submitted because they are found automatically. The Yahoo! Directory and DMOZ, two major directories which closed in 2014 and 2017 respectively, both required manual submission and human editorial review.[39] Google offers Google Search Console, for which an XML Sitemap feed can be created and submitted for free to ensure that all pages are found, especially pages that are not discoverable by automatically following links[40] in addition to their URL submission console.[41] Yahoo! formerly operated a paid submission service that guaranteed crawling for a cost per click;[42] however, this practice was discontinued in 2009.
Having large groups of content that all revolve around the same topic will build more relevance around keywords that you're trying to rank for within these topics, and it makes it much easier for Google to associate your content with specific topics. Not only that, but it makes it much easier to interlink between your content, pushing more internal links through your website.

At our agency, we work with sites of varying sizes, from very large to quite small, and recently, we have noticed a trend at the enterprise level. These sites aren’t relying as much on Google for traffic any more. Not only are they not relying on Google traffic, but also, the sites are getting less than 10 percent (or slightly more) of their organic traffic from the search giant.