1. Thinking that hiring a specialist once will solve your problem.

You get what you pay for, one of the worst #seo mistakes is to buy or hire cheap services.When you hire an SEO firm, you need to use the service on regular basis. SEO is not a one-off work.

2. Bad keyword research.

Trying to rank your site for generic, highly competitive keywords that have had the life squeezed out of them by the big SEO players out there, is like trying to push a boulder up a hill.Another mistake you can make is building spammy links, because it's incredibly difficult to fix this mistake.

3. Bad content or sneaky onsite tactics

Bad links can take months or years to fix. In the end, the only ones who are more "long term" focused end up garnering the long term results. #google will never reward short term solutions and frankly, no smart #search engine would benefit from them either.  

4. Ignoring Google's webmaster rules.

Many SEO experts still ignore all Google rules and do Keywords Stuffing, Low quality link building and spreading Spammy links everywhere. I think these are really bad things for SEOs.

5. High keyword density

There was a time not too long ago when Keyword density was a good thing but with the latest implementation of Google's Panda algoritim this is no longer the case, relevant and minimal usage of select keywords will help you avoid the penalty box with Google.

6. Not making a title tag

The title tagis the single most important on-page SEO element.The <title>tagis required in all HTML documents and it defines the title of the document. Properly writtentitle tagsare critical to your SEO strategy.Title tagstell search engines what your page is about.

7. Following traditional SEO methods is a huge mistake in 2014.

There was a time when doing massive link building and focusing only on getting rank was priorities, its no longer 2009, social engagement and content strategy are needed to create brand awareness.2014 means updating with New Strategies as per Google Updates and Algorithm

8. Duplicated content and poor quality website.

Using duplicate content and making back links from low quality sites is a huge no no. In SEO, like in so many other things, Originality matters, Content Originality specifically Some folks end up copy pasting content,Although there are many other things that can go wrong but Ctrl+ C, is the biggest sin!!!

9. Choosing a keyword based domain.

Google is now promoting brands for keywords.

To ensure your SEO campaigns are high quality Try to avoid the following mistakes:

• Linkbuilding ( Blackhat techniques ) If you must build links do it with credibility, they will last longer and add value.
• Keyword stuffing will kill your site in a heartbeat
• Lot of cheesy advertisements - Destroy credibility
• Block of Ads above the fold - Kill your organic CTA's
• Link selling - Is frowned upon by this establishment and will penalize you severly
• Non User Friendly site -Develop Website for users not for Search Engine. Putting search engines before your users Google will never pay you as well as a loyal, happy audience.