Each point highlighted in a grey is taken directly from the Google Webmaster Guidelines, the descriptions underneath each are intended as practical examples and descriptions of what each means.
Design & Content
Make a site with a clear hierarchy and text links. Every page should be reachable from at least one static text link.
This is a fundamental of website design and information architecture, but it holds very specific meaning for search engine optimization. The major engines use web crawlers to find and index every page on a website, the requirement for this of course is that there are links on your site to every page that you want them to find.
If a page exists on your website, but it has no links pointing at it, that’s often called an “orphaned page”.
The problem with these is twofold: firstly, it makes it very difficult for search engines to find. Submitting a sitemap that contains a reference of that page might let the search engines know it exists, but the second issue is that without links pointing at a page, search engines don’t know how important that page is.
Internal links on a website are how “PageRank” flows around a site, and that’s one of the fundamentals of getting a page to rank well.
Offer a site map to your users with links that point to the important parts of your site. If the site map has an extremely large number of links, you may want to break the site map into multiple pages.
Sitemaps for users are of questionable value in 2014. If you have a good overall site structure then you shouldn’t need a specific sitemap that lists every page on your site. Search engines recommend these however to make sure that they can find all of the pages on your website and if you are having problems with some pages being indexed this can help.
I wouldn’t recommend relying on a user sitemap (or an “XML sitemap” submitted directly to the search engines) to get your pages listed though, as it can often cover up underlying problems with the structure of your website.
If pages aren’t being indexed correctly you might never know if you just rely on user sitemaps.
Keep the links on a given page to a reasonable number.
You should always try and have the lowest number of internal links on a page possible. There are a couple of reasons for this, the most important being PageRank and how it flows around your website.
The more links you have on a page, the thinner the PageRank is spread, with each link having less overall. There are plenty of complex calculations but its really quite simple once you break it down into its purest form:
Each page has a certain amount of strength (PageRank). It passes its strength onto other pages by linking to them, but it only passes a finite amount of strength. That amount is divided by the total number of links on your page, and each URL that is linked to receives a smaller amount if there are lots of links on a page.
Therefore, if you restrict links down to the absolute minimum you can, each remaining page is stronger and will have a better chance or ranking well.
Create a useful, information-rich site, and write pages that clearly and accurately describe your content.
This might sound like a complete no-brainer, but you would be amazed how many times people get this fundamental wrong.
Take a cold hard look at your site, or even better, get someone else to look at it for you and answer honestly the following questions: “why is this site any more useful than every other site covering the same topic?” & “Does this site provide good information that people can not get elsewhere already?“.
If you can’t honestly answer both of those questions, you have to consider why a search engine would consider your pages the right ones to rank in their results – more often than not, the better the information on a site, the more likely it is to rank well. The ultimate example of this being Wikipedia.
The message here is simple: if there is no reason why your site should rank, it probably won’t, no matter what you do.
Think about the words users would type to find your pages, and make sure that your site actually includes those words within it.
This is as close as search engines get to saying that you should think about keywords.
While its true that Google and Bing have got much better, particularly in 2013 understanding the core topics of a webpage and website, its worth remembering that they still function by reading the text on your site and if you want to rank for something, it just makes sense to include those words!
While you should always have good, descriptive text, you should also make sure that the keywords you want to rank for appear in the title of the page itself. These clear signals as to what a page is about are still a great help to search engines.
[well]Try to use text instead of images to display important names, content, or links. The Google crawler doesn’t recognize text contained in images. If you must use images for textual content, consider using the “ALT” attribute to include a few words of descriptive text.
This might not seem absolutely clear at first, but a lot of people still use images instead of titles at the top of pages as they are often easier to style attractively. That’s all well and good for the user, but if you do things like this search engines will struggle to understand what a page is about.
Another common use is to put a persons name under their photo on a web page as part of the image itself. Again, this could be easier to make look stylish, but Google or Bing will really find it hard working out who is in the image!
These days any good web designer can make ‘proper’ text look beautiful, so there really is no excuse these days with web fonts and CSS3.
Make sure that your <title> elements and ALT attributes are descriptive and accurate.
This really isn’t just an SEO requirement, its also a usability requirement.
The <Title> element is normally how your pages appear in search engines (the large link in the snippet), and ALT attributes are attached to images on a web page to give a text description of an image.
If you fail to use ALT attributes on images, people that require the use of screen readers will find it much harder to understand the content of your website. Search engines also depend on these tags to get an idea for what an image is meant to be, and this helps you rank for those terms.
The other consideration, is feature phones and other devices without full web browsers – these devices often rely on ALT tags.
Check for broken links and correct HTML.
HTML is the basic language that all web pages are built with, and websites depend on links to other pages to allow both people and search engines to navigate.
If you have basic errors such as broken links or poorly formatted HTML at best it can give unpredictable results, at worst it might mean that your site doesn’t work as intended and search engines might be inclined to ignore your content.
If you decide to use dynamic pages (i.e., the URL contains a “?” character), be aware that not every search engine spider crawls dynamic pages as well as static pages. It helps to keep the parameters short and the number of them few.
In 2014 search engines are much better than they were just a few years back at understanding dynamic pages (ones that include a question mark in the URL). That however doesn’t excuse actually using them on your site though!
Having short, snappy & descriptive URLs is extremely important for a number of reasons. They are easier for people to remember, share and use. Having question marks in them and query strings instead of keywords just isn’t acceptable or necessary these days so don’t do it.