Deoptimizing - a new way of SEO

I'll start this post with the assumption that you have experienced problems with the new google's ranking algorithms. This means that sometimes your website might appear at the end of search results(950 page) or may be listed as supplemental. One possible reason for this is that it has lost its trustrank and might have the so called 950 penalty applied runtime. So in order to escape here is what might help you.

First check whether you need to deoptimize:
If you want to see all the non-supplemental pages from your just type in google:
site:www.yourwebsite.com/*

Then to see just the supplemental pages from your site type:
site:www.yourwebsite.com/ -site:www.yourwebsite.com/*


What to do:
1. Validate your website
2. If you use plenty of H1,H2,H3 tags remove most of them or replace H1 with H2 tags or with span or strong tags.
3. Don't use same data in: title, h1, meta description tags.
4. In your website inner-linking navigation use same linking structure. Update: using same title attributes in the menu on every page of your site is considered as spam.
5. Your affiliate/referral links should differ in anchor text. Please check the title attributes to be unique and avoid keywords stuffing there.
Update: Pay special attention to title and alt attributes: if they are overstuffed google bot will just place the first few lines of your page as a description in its search results which turns to be your repeating website heading information.
Solution: examine what your search results look like(site:http://www.yourwebsite.com), see what exactly indexes google and make according changes ie. reduce title attributes.
6. Remove any static content from the bottom page of your website especially outbound links, etc...
7. Check your affiliate links whether they are thematic or not. Remove those that are not connected to your site theme or add rel="nofollow" to them. If your site displays RSS feeds be sure to add rel="nofollow" also to them.
8. Deoptimize - lower your content keyword density

http://www.webconfs.com/keyword-density-checker.php

and check your content for spam here:

http://tool.motoricerca.info/spam-detector/

note for blogger users: check out your navigation(posts archive) - too many links to posts with keywords in their titles increases the overall post keyword density so be careful.
when using forms you may also look over your hidden field values: do not use keywords there - it's an easily misunderstood issue.
9. Limit the usage of title attributes in the <a href> tags as well as <b>/<strong> tags -> they weigh to the content presented in the SERPS.
Wait and hopefully soon you'll be out of the google's supplemental index.

These might sound as drastic measures but I've already managed to escape 3 websites using the above techniques. So experiment and look what will happen.
For more information look at:

Is your website in Google's sandbox?

Duplicate website content and how to avoid it