I prefer simple SEO techniques and ones that can be measured in some way. I have never just wanted to rank for competitive terms; I have always wanted to understand at least some of the reasons why a page ranked for these key phrases. I try to create a good user experience for humans AND search engines. If you make high-quality text content relevant and suitable for both these audiences, you’ll more than likely find success in organic listings and you might not ever need to get into the technical side of things, like redirects and search engine friendly URLs.
QUOTE: “For years, the user experience has been tarnished by irritating and intrusive ads. Thanks to extensive research by the Coalition for Better Ads, we now know which ad formats and experiences users find the most annoying. Working from this data, the Coalition has developed the Better Ads Standards, offering publishers and advertisers a road map for the formats and ad experiences to avoid.”  Kelsey LeBeau, Google 2019
QUOTE: “I think there is probably a misunderstanding that there’s this one site-wide number that Google keeps for all websites and that’s not the case.  We look at lots of different factors and there’s not just this one site-wide quality score that we look at. So we try to look at a variety of different signals that come together, some of them are per page, some of them are more per site, but it’s not the case where there’s one number and it comes from these five pages on your website.” John Mueller, Google 2016

Google engineers are building an AI – but it’s all based on simple human desires to make something happen or indeed to prevent something. You can work with Google engineers or against them. Engineers need to make money for Google but unfortunately for them, they need to make the best search engine in the world for us humans as part of the deal. Build a site that takes advantage of this. What is a Google engineer trying to do with an algorithm? I always remember it was an idea first before it was an algorithm. What was that idea? Think “like” a Google search engineer when making a website and give Google what it wants. What is Google trying to give its users? Align with that. What does Google not want to give its users? Don’t look anything like that. THINK LIKE A GOOGLE ENGINEER & BUILD A SITE THEY WANT TO GIVE TOP RANKINGS.
While many shy away from this topic, it’s actually not the scary monster many make it out to be. Actually, Wix has the best SEO and you can very easily use its power for your own website. The first step in the right direction is to use the new, free and very efficient Wix SEO Wiz – a user-friendly tool that will take you step-by-step through the process of optimizing your website.

QUOTE: “If you have a manual action against your site for unnatural links to your site, or if you think you’re about to get such a manual action (because of paid links or other link schemes that violate our quality guidelines), you should try to remove those links from the other site. If you can’t get these links removed, then you should disavow those links to your website.“ Google Webmaster Guidelines 2020

QUOTE: “… it also includes things like the comments, includes the things like the unique and original content that you’re putting out on your site that is being added through user-generated content, all of that as well. So while I don’t really know exactly what our algorithms are looking at specifically with regards to your website, it’s something where sometimes you go through the articles and say well there is some useful information in this article that you’re sharing here, but there’s just lots of other stuff happening on the bottom of these blog posts. When our algorithms look at these pages, in an aggregated way across the whole page, then that’s something where they might say well, this is a lot of content that is unique to this page, but it’s not really high quality content that we want to promote in a very visible way. That’s something where I could imagine that maybe there’s something you could do, otherwise it’s really tricky I guess to look at specific changes you can do when it comes to our quality algorithms.” John Mueller, Google 2016

QUOTE: “Over time, we’ve seen sites try to maximize their “search footprint” without adding clear, unique value. These doorway campaigns manifest themselves as pages on a site, as a number of domains, or a combination thereof. To improve the quality of search results for our users, we’ll soon launch a ranking adjustment to better address these types of pages. Sites with large and well-established doorway campaigns might see a broad impact from this change.” Google, 2015
Search engines use complex mathematical algorithms to interpret which websites a user seeks. In this diagram, if each bubble represents a website, programs sometimes called spiders examine which sites link to which other sites, with arrows representing these links. Websites getting more inbound links, or stronger links, are presumed to be more important and what the user is searching for. In this example, since website B is the recipient of numerous inbound links, it ranks more highly in a web search. And the links "carry through", such that website C, even though it only has one inbound link, has an inbound link from a highly popular site (B) while site E does not. Note: Percentages are rounded.
As of 2009, there are only a few large markets where Google is not the leading search engine. In most cases, when Google is not leading in a given market, it is lagging behind a local player. The most notable example markets are China, Japan, South Korea, Russia and the Czech Republic where respectively Baidu, Yahoo! Japan, Naver, Yandex and Seznam are market leaders.
QUOTE: “high quality content is something I’d focus on. I see lots and lots of SEO blogs talking about user experience, which I think is a great thing to focus on as well. Because that essentially kind of focuses on what we are trying to look at as well. We want to rank content that is useful for (Google users) and if your content is really useful for them, then we want to rank it.” John Mueller, Google 2015
QUOTE: “Some pages load with content created by the webmaster, but have an error message or are missing MC. Pages may lack MC for various reasons. Sometimes, the page is “broken” and the content does not load properly or at all. Sometimes, the content is no longer available and the page displays an error message with this information. Many websites have a few “broken” or non-functioning pages. This is normal, and those individual non-functioning or broken pages on an otherwise maintained site should be rated Low quality. This is true even if other pages on the website are overall High or Highest quality.” Google
QUOTE: “The preferred domain is the one that you would liked used to index your site’s pages (sometimes this is referred to as the canonical domain). Links may point to your site using both the www and non-www versions of the URL (for instance, http://www.example.com and http://example.com). The preferred domain is the version that you want used for your site in the search results.” Google, 2018
Critics will point out the higher the cost of expert SEO, the more cost-effective Adwords becomes, but Adwords will only get more expensive, too. At some point, if you want to compete online, your going to HAVE to build a quality website, with a unique offering to satisfy returning visitors – the sooner you start, the sooner you’ll start to see results.
QUOTE: “The average duration metric for the particular group of resources can be a statistical measure computed from a data set of measurements of a length of time that elapses between a time that a given user clicks on a search result included in a search results web page that identifies a resource in the particular group of resources and a time that the given user navigates back to the search results web page. …Thus, the user experience can be improved because search results higher in the presentation order will better match the user’s informational needs.” High Quality Search Results based on Repeat Clicks and Visit Duration

Many blogging software packages automatically nofollow user comments, but those that don't can most likely be manually edited to do this. This advice also goes for other areas of your site that may involve user-generated content, such as guest books, forums, shout-boards, referrer listings, etc. If you're willing to vouch for links added by third parties (for example, if a commenter is trusted on your site), then there's no need to use nofollow on links; however, linking to sites that Google considers spammy can affect the reputation of your own site. The Webmaster Help Center has more tips on avoiding comment spam40, for example by using CAPTCHAs and turning on comment moderation.

SEO techniques can be classified into two broad categories: techniques that search engine companies recommend as part of good design ("white hat"), and those techniques of which search engines do not approve ("black hat"). The search engines attempt to minimize the effect of the latter, among them spamdexing. Industry commentators have classified these methods, and the practitioners who employ them, as either white hat SEO, or black hat SEO.[50] White hats tend to produce results that last a long time, whereas black hats anticipate that their sites may eventually be banned either temporarily or permanently once the search engines discover what they are doing.[51]

When I think ‘Google-friendly’ these days – I think a website Google will rank top, if popular and accessible enough, and won’t drop like a f*&^ing stone for no apparent reason one day, even though I followed the Google SEO starter guide to the letter….. just because Google has found something it doesn’t like – or has classified my site as undesirable one day.

However, if possible, I would like you to expand a bit on your “zombie pages” tip..we run a site where are definitely enough pages to delete (no sessions, no links, probably not even relevant with the main theme of the site, not even important for the architecture of the site)..Nonetheless, I am not very sure what is the best technical decision for these pages…just deleting them from my CMS, redirecting (if there is a relevant alternative) or something else? Unindex them on Search console? what response code they should have? ..