You can’t remember everything especially with that huge amount of new information we consume daily. It is always great to have a few sheets that list most essential data we often need to deal with (along with SEO tools). Below I am listing a few cool cheat sheets most SEOs will find useful:

SEO Cheat Sheet

The Web Developers SEO Cheat Sheet (or preview it on Scribd) include:

• Important SEO HTML tags;
• Search engine indexing limits (common indexing limits imposed by search engines on sites that don’t hold a lot of authority);
• Recommended title tag syntax;
• Common canonical issues;
• Important search engine robot user-agents;
• Common robot traps to avoid (how webmasters might unintentionally stop spiders from crawling their sites);
• Robots Meta tag syntax;
• Robots.txt syntax;
• Sitemap syntax.

HTML Cheat Sheets

Html and Xhtml cheat sheets – this page contains a number of must-have PDF documents to quickly remind you of proper tag. All of them are very well designed and contain huge amounts of data on one page. For more basic info on HTML you might also want to bookmark or print this page.

Search Cheat Sheet

Search Engine Operators: this cheat sheet contains all essential advanced search operators for Google, Yahoo and MSN. Besides that, it lists some sample queries to search for backlink opportunities, forums and directories (Note: it hasn’t been updated since 2007, so some data can be outdated, e.g. the hack for supplemental results does not work any more).

Here is also a decent Google advanced search sheet and (on the side note) Gmail shortcuts sheet.

Usability Cheat Sheet:

25 point Website Usability Checklist: keep this list at hand when planning a new website or evaluating an existing one. It lists most traditional usability and accessibility issues and basic recommendations. It is both important and measurable. The list is split into 4 roughly equal sections, (I) Accessibility, (II) Identity, (III) Navigation, and (IV) Content with 3 basic ratings: (1) Green Check = Good/Pass, (2) Red Check = Needs work, but no disaster, (3) Red X = Bad/Fail. Not all points are necessarily applicable to all sites.

WordPress Cheat Sheet

WordPress Cheat Sheet (pdf) lists some essential php hacks to customize your theme (if you can’t do that with a plugin of course).

Mod_rewrite Cheat Sheet

The mod_rewrite cheat sheet is a one-page reference sheet, listing flags for the RewriteRule and RewriteCond directives, list of server variables, a regular expression guide and several examples of common rules.

htaccess Cheat sheet

htaccess cheatsheet lists some very basic but frequently-used htaccess hacks.

Source: searchenginejournal , thejackol ,addbyte,wpcandy,usereffects,