Search engine robots crawl the web and create an index. And it doesn’t hurt to help them a bit. Yoast SEO rolls out the red carpet for the search bots, making it super easy to crawl your site and find everything. Basically, the WordPress plugin takes care of all the technical stuff for you. But hey, if technical tweaking is your thing – more power to you. With Yoast SEO, you can edit your robots.txt and .htaccess files, clean up your URLs and generate and update your sitemaps.
Yes, you need to build links to your site to acquire more PageRank, or Google ‘juice’ – or what we now call domain authority or trust. Google is a link-based search engine – it does not quite understand ‘good’ or ‘quality’ content – but it does understand ‘popular’ content. It can also usually identify poor, or THIN CONTENT – and it penalises your site for that – or – at least – it takes away the traffic you once had with an algorithm change. Google doesn’t like calling actions the take a ‘penalty’ – it doesn’t look good. They blame your ranking drops on their engineers getting better at identifying quality content or links, or the inverse – low-quality content and unnatural links. If they do take action your site for paid links – they call this a ‘Manual Action’ and you will get notified about it in Google Search Console if you sign up.
Your site’s URL structure can be important both from a tracking perspective (you can more easily segment data in reports using a segmented, logical URL structure), and a shareability standpoint (shorter, descriptive URLs are easier to copy and paste and tend to get mistakenly cut off less frequently). Again: don’t work to cram in as many keywords as possible; create a short, descriptive URL.

Try and get links within page text pointing to your site with relevant, or at least, natural looking, keywords in the text link – not, for instance, in blogrolls or site-wide links. Try to ensure the links are not obviously “machine generated” e.g. site-wide links on forums or directories. Get links from pages, that in turn, have a lot of links to them, and you will soon see benefits.

QUOTE: “To summarize, a lack of helpful SC may be a reason for a Low quality rating, depending on the purpose of the page and the type of website. We have different standards for small websites which exist to serve their communities versus large websites with a large volume of webpages and content. For some types of “webpages,” such as PDFs and JPEG files, we expect no SC at all.” Google Search Quality Evaluator Guidelines 2015
QUOTE: “Important: The Lowest rating is appropriate if all or almost all of the MC (main content) on the page is copied with little or no time, effort, expertise, manual curation, or added value for users. Such pages should be rated Lowest, even if the page assigns credit for the content to another source.” – Google Search Quality Evaluator Guidelines 2019
Being ‘relevant’ comes down to keywords & key phrases – in domain names, URLs, Title Elements, the number of times they are repeated in text on the page, text in image alt tags, rich markup and importantly in keyword links to the page in question. If you are relying on manipulating hidden elements on a page to do well in Google, you’ll probably trigger spam filters. If it is ‘hidden’ in on-page elements – beware relying on it too much to improve your rankings.

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? ..