David Letterman Style, here it is:
#10. You're optimizing your website around really common (probably really popular) keywords that you'll never be able to rank for. In the last week, I've had two people tell me they wanted to optimize their site around "leadership". I said, good luck competing with Wikipedia and About.com.
#9. Everyone of your title tags has the same keyword phrase in it. And it's your company name. The title tag on a page is probably the most important On-Page SEO factor to consider when creating new pages. You probably already rank well for a search on your company name, so you can safely leave that out and still get that traffic. So, make sure you pick appropriate keyword phrases for each page that are phrases that someone is going to type into a search engine in order to find a product or service like yours.
#8. Dynamic URLs without your keywords in it. You bought a fancy shopping cart or content management system (CMS) that uses dynamic urls with all kinds of random numbers and random letters in the url. Your URLs should be readable by humans because search engines read words like humans too. The words in your URLs is another very important signal to search engines what that page is about. So, get yourself a CMS that allows you to control your urls or get yourself a URL rewriter. Include your keywords in your URLs.
#7. You used images as headings. Headings are usually the big bold letters right above the content at the top of a page usually below your navigation. See "HubSpot Inbound Internet Marketing Blog". That's a heading. If these are "words built with images" (designers do this to control the font of the text), search engines aren't reading them. These should be text. Pick a web safe font that's close to what you want. Go with that.
#6. Number 6 is equally egregious, but a little less common nowadays unless your website is circa 1997... If your navigation is built using image buttons instead of text, you're giving search engine one less signal about what that page is about. See #7 for a fix: Use text.
#5. All of the above. I've seen it happen. I've seen sites with all of the above mistakes. Really. Honest.
#4. Doing SEO after the website is designed and built. For some reason, people think SEO should start afterwards. I've been racking my brain for an analogy, but it's really pretty simple: Do you go on a trip before you pack? Do you launch a business before writing some sort of business plan? Do you visit to a friend's new house without printing out driving directions?
SEO done right allows you to determine what content to write in order to get traffic from search engines. And you shouldn't design a site before you know what content will be on it. I'm not saying that you should change your business model or product name based on what keywords will be easiest to rank for, but you should consider it. I guarrantee you that your competitors or smart internet marketers are doing this homework. Why not claim the search traffic for your business? It only takes a little bit of planning.
Plus, if you go to a designer or web developer that isn't an expert at SEO (Most aren't - even though they say they are), they may not implement a system that allows you to publish new pages and optimize your site around your keywords without paying them $100/hour to make the changes and additions for you. Someone that knows SEO will launch your website in a system that allows you to easily do SEO on a continous basis.
Which brings us to...
#3. Our design firm "DID" SEO for us. This one is probably the most common. There is no such thing as "BEING DONE" with SEO. It's an ongoing thing. Just the other night, I logged into HubSpot's Keyword Grader tool and found 2 new keywords that we should target. We rank not-quite-on-the-first-page for both of them and both of them could deliver several several hundred visitors/month once we get to the first page. That's hundreds more visitors we could attract to our site - with a bit of effort. And we already rank for "internet marketing", "internet marketing software" and a bunch of other great phrases that are relevant to our business. Doing SEO once is like doing prospecting once. If your salesperson said "I called prospects last month" as a reason for not calling any new prospects this month, what would you say to them right before you fired them?
#2. You built your website entirely in flash. You might as well put an invisible shield up between you and the search engines because they don't see you.
#1. And the number one most egregious mistake. Drumroll, please... Your site is built entirely in flash, you're a web design firm and you advertise that you do SEO. I've run into two of these people recently. I won't link to them even though they deserve to be called out.
*Originally posted by Pete Caputa - Internet Marketing for HUBSPOT.COM