Site optimization recommended by Google

To help webmasters improve the position and presentation of their site in CERP, Google posted a best practices file online.

This PDF file (in English) can be downloaded and printed, here is a summary of it.

I - Search Results Overview

To improve the way a link is presented on your page, you can use the <title> tag, description and other meta tags, as well as the organization of the titles.

Name

The statistical reality is as follows:

68% of titles simply contain product name, themes
20% of titles have a product name plus data not directly related to it
10% of titles have a product name plus key
1% contain non-descriptive content
1% describe something other than content

The name can be 60 characters long. It needs to be used. It must contain product keywords (in one sentence).

The title should be a summary of the description: some users only look at the title.

The title and meta-description should have descriptive content to inform users. We need to think about what users are looking for.

Meta tag: The noodp tag in <meta robots content =" noodp"> prevents the use of a Dmoz.org name and description.

Description

It is contained in the <meta name = "description" content = "">. Its length must match two rows of results page fragments.

67% of pages do not have a description tag
Only 33% have a lighthouse

The content of this tag can be used for the results page, and this is necessary when the page contains little text (especially images).
It may also allow for a description that may create user interest. She describes the content and what is useful to him.

Production of sitelinks

You can facilitate the appearance of links to the site under the heading and snippet in SERPs .

56% of results have no situlae
44% have them.
30% have them, but they are not descriptive

To get a better chance:

Multi-level site structure.
Internal links have the descriptive wording of the linked page.
Not too many subdirectories, too deep pages.

If sitelinki are not relevant, they can be blocked in webmaster tools (GWT).

II - URLs and redirects

To avoid duplicate content, use the <link rel = "canonical" href = ""> tag.

41% use product/project/topic subdirectories
29% use subdomain
30% are files on the primary domain

For those who use the subdirectory.

19% no slash at the end
5% with slash and redirection to index file, which is correct
15% without slash and redirect 301 in a subdirectory or file, which is correct .

III - Page Optimization

What can be optimized:

For logo, alt attribute, and link.
Titles and subtitles.
Image file names.
Content and keywords.
Labels of internal links (anchors).

Securities

61 pages contain text headings (not images).
29 % do not have them.
35% do not have a <h1> tag

Headings should contain a description of the content of the sections and keywords.

The <h1> tag should be used for the main title of the page and should reflect its overall content .

Logo

59% of logos do not have a link on the site
Only 38% have a link, which is a canonical link on the homepage.
18% do not have alt attribute

Logo image must contain alt attribute. The content of the site is similar to the name of the site (home page).

Internal communications

67% of internal links have a descriptive wording (binding) of the linked page.
33% have a generic wording (for example, "Learn more," etc.).

The text should have a similar description in the title of the linked page. All the rules of the name also apply to it.

Links

Google's SEO Report Card. Full document in English
Happy and canonical duplicate. Penalties for duplicating content and using a tag to avoid them.