With each Google algorithm update the SEO world changes. Obviously, getting found and a good ranking is a constant concern of all web site operators. Searchenginewatch.com offers some valuable tips on how you can keep an eye on the most important factors you should keep checking at regular intervals to avoid that your ranking drops with the next Google update.
1. Titles and Descriptions
Titles and descriptions still remain one of the most misunderstood items on any site and they are still as important as ever. Know what these mean and how to write each properly. Make sure you don't have duplicates, ones that are too long or over-optimized tags.
2. Anchor Text
Is your anchor text over-optimized with keywords? Are you using keywords when domain names should be used? What is the natural way someone would link to your site? This counts with inbound links as well as internally. Beware of over-optimized and overused keyword anchor text.
3. Links – Inbound & Outbound
Run a link check. How do your inbound links look? The threshold for spammy links was about 80% it is now down to about 50%. That means 50% questionable links can keep your site or a page out of the index. Besides, when using outbound links, make sure you are not sending out link juice on ad links, but still make sure you are doing some links offsite. Google doesn't like it when you hoard that link power all for yourself. Share with worthwhile sites, but never with ad links.
4. Links Cross or Triangulate
Sometimes by accident even, sites crosslink to other sites they own or partner with that site while sitting on the same IP addresses or C classes. Do you know if yours do? If they do, delink your sites or put rel=nofollow on those links, or Google may think you are attempting to put up a link network of your own. Remember, Google can't discern intent, so the appearance of impropriety is all that you need to give yourself a penalty.
5. Page Speed
Google likes to say page speed is a small factor for websites and maybe for some industries this is the case, but in others our experience shows it isn't. This only makes sense. For Google, faster loading sites lower the load on Google's end, so take the page speed tool, check your site, and get it above a 90% if you can. That seems to be the magic threshold for most.
6. User-Generated Content Spam
User-generated content spam on your site is directly linked to a penalty now at Google. Thus, make sure you have checked your blogs and comment areas for things like multiple https or for words such as "free shipping" with a database crawler or in Google with site:domain.com "words go here" and see if someone is scamming you.
Get a tool like Screaming Frog and check your site pages for redirects then make sure those redirected pages have a 301 permanent redirect, which tells Google the page has been permanently moved and it should keep following it. It's rare you need a different type of page redirect and if you do, then remove the page from the index with a noindex tag in the header. Also make sure you have your canonicals in place and that they are correct. This should go without saying, but not all sites do it.
8. Over-Optimization on Non-Content Items
A common type of over-optimization happens in the navigation, the header or footer. This is where someone either adds a keyword to almost every word to try to rank for the term or where someone adds an overabundance of header or footer links to "help" a site position for known keywords. This won't help and is likely to give the site a penalty.
9. Alt Attributes
How are you using the alt attribute on your images? Don't stuff keywords into this text. Using good alt text, especially when images are replacing text in links, can be very good for a site. In fact, Google will treat this alt text as actual text in these cases. Go to http://webaim.org to learn the rules for "alt text" content generation.
10. Ad Issues
Google doesn't like it when a site seems to only be there to support the ads on it, so an overabundance of above the fold ads can cause the site to receive a penalty.
11. Crawl Issues
When is the last time you got into your Webmaster Tools and checked how your crawls were going? How is your crawl rate? Are the spiders having any crawl issues? Find the answers, as it will affect your site strength and authority with the "No One Is Home" devaluations. Keep an eye on your crawl rate and if it is not crawling well, find out why as quickly as possible and fix it!
12. Malware or Rogue Sites
For the most part, we're fortunate that Google will email us and tell you that you have malware on your site – but be careful: this isn't always the case. Periodically you want to do a search for your site, see if you trigger malware warnings in a site search or mobile, then check your analytics to make sure no one is running anything untoward on your site like say a rogue Viagra site. If you want to see how prevalent this is, go to Google search and put in ".gov" Viagra. Not only can these sites be doing things on your site that could be causing you "hack" issues, but also sending links to their pages on your site causing your link profile to be damaged.
This was just a partial list to get you started, as searchenginewatch.com did not even touched authorship, structured data, URL construction or a whole lot of things you should be checking, but hopefully you get an idea that myopic SEO is not SEO at all. So, be proactive, as only a small percentage of sites hit by the first Penguin have ever fully recovered.
By Roger Stadler