Key words optimization of the good and bad

Under normal circumstances, we can optimize how a site words, primarily by the following:
1. The size of the site, and the resulting decision of the keywords location.
2. Keywords in the distribution of the site.
3. Keywords expansion of the mining and use.
4. Home page, directory pages, the content of the page title tag is written norms.
5.Description Tag-description tag, keyword tags, ALT-lieu of property, such as whether it is reasonable to use.
6. Keywords as well as the density of words on the page.
7. Keywords fonts, special.
8. The existence of superimposed words, the hidden text and links, such as cheating.