You'll find a small list of things to do when you create a website and expect to generate traffic. This would cause a penalty or a loss of SEO juice.
1) No text in the picture: a common mistake to avoid! Content is king in search engine optimization. With CSS3 and html5, you can create beautiful fonts that can be indexed. But if you use it in pictures / images, it's a missed opportunity! Especially in your logo / slogans
2) No advertising: if you can afford not to place advertising on your website. This would devalue your website as this would have an impact on the user experience. Start the website without advertising, you will not win much at the beginning anyway and place it when you have gained authority
3) OBL (outgoing links) low quality / useless / irrelevant: Outgoing links can be considered as an authority leak of your website. Share your SEO juice with the website you want to share and do it carefully.
4) Cross links / reciprocal links: these two practices are oldschool and obsolete for years. The overlaps do not help and the reciprocal links can cause you penalties. It's pretty easy to spot for Google. However, in multi-level links, it's another story. But I'll do a post about it later.
5) No Flash content: Flash is a crime punishable by the death penalty since HTML 5 was released! Avoid it at all costs except for embedding videos. The content is poorly indexed and there is no trend likely to improve the indexing process as HTML 5 is about to explode.
6) No stuffing keywords: Minimize your keywords in meta tags or the content is so old game and it will not work at all. You can make sure that you will have a penalty by doing it
7) No dilution of keywords: Near the practice above, it involves diluting a keyword stuffing into a text instead of a comma. Google has been pulling semantic statistics for years, indexing billions of pages. Therefore, even if there is no ideal keyword density, a dilution of the keywords will be detected and will immediately result in a penalty. This was a method used just after filling the keywords of the early 00's
8) No camouflage / JS links / Door / Invisible text: All these practices are obsolete or you really need to know what you are doing. Camouflage can be done but your method must be precise and you must be ready to evolve all the time. If you get caught once, your website will be permanently destroyed. For me, it is advisable not to use at all costs.
9) No iframe content: Do not be indexed, avoid it unless it brings serious value to your visitors.
10) No pixel links: Google also forbids small and tiny links placed under a 1-pixel image. Even though the page rank is flowing through the images, Google is able to extract the size of your image.
11) No meta-refresh: Meta-refresh is a way to redirect a page to another after a given period of time. It decreases the bounce rate and can be likened to cheating, especially when it is worn on more than one page. It must be used for very specific and defined reasons
12) No Dynamic URL / Session ID: Dynamic URL such as page.php? Login = user name; the password must be deindexed manually to avoid any type of duplicate content or even breach of security.
13) No major structural problems: the website must be structured correctly in HTML with its own "grammar" required. Even if the website is displayed correctly, there may be some structural issues that cause confusion on the part of the search engines.
That's not all, but it remains a good list of things I check first when I have to rank a website for a customer. Avoid them at all costs, unless you are an expert and you are absolutely certain of what you are doing.
I have a paid subscription on developer.apple.com, but for some reason I can not find a way to install the new iOS 13 beta profile. Am I doing something wrong …? This is what the page looks like when I open it on Safari …? o_O (there is no download / install button)