Search engine optimization (SEO) is often about making small modifications to parts of your website. When viewed individually, these changes might seem like incremental improvements, but when combined with other optimizations, they could have a noticeable impact on your site's user experience and performance in organic search results. You're likely already familiar with many of the topics in this guide, because they're essential ingredients for any web page, but you may not be making the most out of them.
QUOTE: “Fixing the problem depends on the issue you have. For example, if it’s a pop-up, you’ll need to remove all the pop-up ads from your site. But if the issue is high ad density on a page, you’ll need to reduce the number of ads. Once you fix the issues, you can submit your site for a re-review. We’ll look at a new sample of pages and may find ad experiences that were missed previously. We’ll email you when the results are in.” Google, 2017
I do not obsess about site architecture as much as I used to…. but I always ensure my pages I want to be indexed are all available from a crawl from the home page – and I still emphasise important pages by linking to them where relevant. I always aim to get THE most important exact match anchor text pointing to the page from internal links – but I avoid abusing internals and avoid overtly manipulative internal links that are not grammatically correct, for instance..
to avoid throwing link equity away, you might create HIGH-LEVEL IN-DEPTH TOPIC PAGES on your site and redirect (or use canonical redirects) any related expired content that HAVE INCOMING BACKLINKS, to this topic page (and keep it updated, folding content from old pages, where relevant and there is traffic opportunity, to create TOPIC pages that are focused on the customer e.g. information pages)
QUOTE: “The score is determined from quantities indicating user actions of seeking out and preferring particular sites and the resources found in particular sites. *****A site quality score for a particular site**** can be determined by computing a ratio of a numerator that represents user interest in the site as reflected in user queries directed to the site and a denominator that represents user interest in the resources found in the site as responses to queries of all kinds The site quality score for a site can be used as a signal to rank resources, or to rank search results that identify resources, that are found in one site relative to resources found in another site.” Navneet Panda, Google, 2015
Google expects pages to “be edited, reviewed, and updated on a regular basis” especially if they are for important issues like medical information, and states not all pages are held to such standards, but one can expect that Google wants information updated in a reasonable timescale. How reasonable this is, is dependent on the TOPIC and the PURPOSE of the web page RELATIVE to competing pages on the web.

Flash is a propriety plug-in created by Macromedia to infuse (albeit) fantastically rich media for your websites. The W3C advises you avoid the use of such proprietary technology to construct an entire site. Instead, build your site with CSS and HTML ensuring everyone, including search engine robots, can sample your website content. Then, if required, you can embed media files such as Flash in the HTML of your website.
Google expects pages to “be edited, reviewed, and updated on a regular basis” especially if they are for important issues like medical information, and states not all pages are held to such standards, but one can expect that Google wants information updated in a reasonable timescale. How reasonable this is, is dependent on the TOPIC and the PURPOSE of the web page RELATIVE to competing pages on the web.
For instance, in a recent test (2019), if you have a page title longer than 12 words, all the keywords beyond 12 words evaporated from the page copy. This is a change from the way Google used to work, when the extra words were included as part of the page copy, not just part of the title. So, if you have a 15 word title, the last 3 words will not count towards ranking, if that test result was to be replicated.
QUOTE: “common with forums is low-quality user-generated content. If you have ways of recognizing this kind of content, and blocking it from indexing, it can make it much easier for algorithms to review the overall quality of your website. The same methods can be used to block forum spam from being indexed for your forum. Depending on the forum, there might be different ways of recognizing that automatically, but it’s generally worth finding automated ways to help you keep things clean & high-quality, especially when a site consists of mostly user-generated content.” John Mueller, Google

A navigational page is a simple page on your site that displays the structure of your website, and usually consists of a hierarchical listing of the pages on your site. Visitors may visit this page if they are having problems finding pages on your site. While search engines will also visit this page, getting good crawl coverage of the pages on your site, it's mainly aimed at human visitors.
Let’s look at an example. At Yoast, we call our courses platform the “Yoast Academy.” So at first, it might seem logical for us to optimize for the keyword “Yoast Academy.” However, when we analyze traffic data, it turns out that our audience searches for “Yoast courses” way more often. So it makes much more sense to optimize for that term instead. Every company has its internal vocabulary, which often doesn’t match the vocabulary of its audience. Therefore, you should always select your keywords from your audience’s perspective. You can use Google Trends to research how often certain search terms are used compared to other terms.
However, you may encounter pages with a large amount of spammed forum discussions or spammed user comments. We’ll consider a comment or forum discussion to be “spammed” if someone posts unrelated comments which are not intended to help other users, but rather to advertise a product or create a link to a website. Frequently these comments are posted by a “bot” rather than a real person. Spammed comments are easy to recognize. They may include Ads, download, or other links, or sometimes just short strings of text unrelated to the topic, such as “Good,” “Hello,” “I’m new here,” “How are you today,” etc. Webmasters should find and remove this content because it is a bad user experience.
If you have a commenting system (like Drupal, Joomla or WordPress) that allows for search engine friendly links (commonly called dofollow links) from your blog or site, you will probably, eventually be the target of lots of spam, be complicated in tiered link schemes and potentially fall foul of Google’s webmaster guidelines on using the attribute in certain situations.
Mobile-first design has been a best practice for a while, and Google is finally about to support it with mobile-first indexing. Learn how mobile-first indexing will give digital marketers their first real swing at influencing Google’s new AI (Artificial Intelligence) landscape. Marketers who embrace an accurate understanding of mobile-first indexing could see a huge first-mover advantage, similar to the early days of the web, and we all need to be prepared.
Big sites can rank for the most general terms. Smaller sites within a very specific niche can do the same. Of course, it’s also easier if you’re writing in a language that is not spoken all over the world. For most smaller sites that are writing in English, however, the general rule of thumb is this: start with a big set of long tail keywords which have little traffic, but you can rank for more easily. Then, work yourself up to the rankings step-by-step. Once you’ve gained some SEO authority, start optimizing for more general keywords. And in the end, maybe you will even be able to rank for your head keywords!
Link building is not JUST a numbers game, though. One link from a “trusted authority” site in Google could be all you need to rank high in your niche. Of course, the more “trusted” links you attract, the more Google will trust your site. It is evident you need MULTIPLE trusted links from MULTIPLE trusted websites to get the most from Google in 2020.
Make it as easy as possible for users to go from general content to the more specific content they want on your site. Add navigation pages when it makes sense and effectively work these into your internal link structure. Make sure all of the pages on your site are reachable through links, and that they don't require an internal "search" functionality to be found. Link to related pages, where appropriate, to allow users to discover similar content.
Ask for explanations if something is unclear. If an SEO creates deceptive or misleading content on your behalf, such as doorway pages or "throwaway" domains, your site could be removed entirely from Google's index. Ultimately, you are responsible for the actions of any companies you hire, so it's best to be sure you know exactly how they intend to "help" you. If an SEO has FTP access to your server, they should be willing to explain all the changes they are making to your site.