1) Technical part.
The promoted resource should work reliably and quickly and be convenient and understandable for all users. This is the basic necessary condition that we check first. If it’s not observed or not fully observed, the efficiency of other SEO actions may be critically insignificant, and the conversion of traffic attracted by SEO may be questionable. Therefore, if we find problems of this nature, we report them to the customer and provide the solution, or at least insist on providing, if our participation is not stipulated by the contract.2) The content.
Users visit the site in search of the content. Therefore, if the quality of the found content doesn’t suit them — no SEO tricks will help, the target traffic to the site will not grow or its growth will be formal, meaningless, without proper conversion of this traffic into commercial or other desired result. Therefore, the quality of content on the promoted resource is the second fundamental condition for successful SEO. Surprisingly, the content doesn’t even have to be indexed properly (although it is still very desirable); but the content should meet the expectations of the users of the site. We pay the closest attention to this: if the technical part can be done "once and for all" (with certain reservations), then the content has to be dealt with constantly. This is the most important part of our work. And, of course, we are not talking about "SEO content" in its traditional negative sense, meaning texts, images, etc., which somehow are only suitable for attracting search engines, but are practically not interesting and not useful to people. We are creating completely different materials, of an expert level — in the expectation that they will arouse the interest and attention of human users, sufficient for these materials to be distributed naturally: quoted, copied to other resources, popularized with links to the original source, etc.3) External optimization.
In this area, we follow the same approach as outlined in the paragraph above. We consider any external resources that can improve the SEO of the customer's site as platforms that we can share the value with as well, and that's the only reason we feel rightfully entitled to ask for something useful for the customer's site - justifying a link, recommendation, repost or simply mentioning the brand. This ensures not only the ethics or fair validity of the recommendation of a third-party resource, but also makes the link "alive and working", because human users make transitions through it - which is what the search engines see and appreciate.