In many ways, search engine optimisation is like plumbing. Sure anyone can do it, its not rocket science, but to do a good job, you need four basic things:

1. The Knowlegde
   You need to know a bit about the subject. You can easily find out everything you need to know online thesedays. If you do not have the time (or the interest) to find out everything you need to know, then you can always call on the expertise of a tradesman, however calling in the experts is never a cheap option, so if you think you can do it yourself, then you should consider DIY SEO.

   With search engine optimisation, you need to keep updated with new developments and changes in the rules about what constitutes good practice and bad practice (also referred to as ‘white hat’ seo and ‘black hat’ seo – a phrase derived from the old cowboy films where the goodies always wore white hats and the baddies always wore black hats). For example, paying for links on someone else’s website was seen as a good business model in the early days of SEO, and a lot of people made a lot of money out of it.

   These days, you can get penalised by Google for paying for links. Where this puts services like Yahoo directory, which is a paid-for link directory, I dont know, but there is good evidence to suggest that inclusion in the Yahoo directory actually increases your site’s trust rank in google. (Very few spammers would fork out hundreds of pounds to Yahoo just to get one low converting link).

   To arm yourself with the right knowlege, you need to first know the basics of SEO – there are quite a few articles online which give a good a general background in SEO. A quick search for the phrase ‘SEO introduction’ or ‘SEO tutorial’ will allow you to find them easily.

   Note: no one outside google know exactly what factors and what weighting each factor of a webpage determines page rank, and opinions on certain things differ - like whether div layers or tables get better rankings, or whether using noscript tags penalise your page, so it is a good idea to read these articles with the view that they represent evidence based theories rather than actual facts. 

2. The Tools
   In order to maximise your time, you need to make sure you are using the right tools. You wouldn’t use a sink plunger to fit a tap now would you? Similarly, with search engine optimisation, you need to use the right tool for the job. There are lots of online tools to checking keyword positions, domain ages, online search engine submissions etc. Again, the rule of thumb is if they appear high up in Google for ‘SEO Tools’ then they probably work.
3. The Experience
   The more you do something, the better you get at it. Writing descriptive, keyword rich page titles that are attractive to human activity in search engines is a fine art. Vetting partner site quality for link exchanges or finding good free directory sites to submit your url to also gets easier and quicker with practice. 
4. The Time
   Lets face it, if you had a spare 4 hours a day to promote your site, research keywords, analyse web traffic and generate updated content for your website, you would probably be on page 1 of google for most of your targeted keywords, but in the real world, most people and businesses do not have time for this, which is why some companies employ SEO consultants or search engine optimisation companies to do this job for them.

   Larger companies often have experts in-house to perform this function. All too often though, the role of SEO in larger companies is attached as a secondary roll to a technical team or web designers. Sometimes this is a good idea since SEO for a single small scale website is not generally a full time job.
    

Should you DIY SEO?

The answer to this question depends on whether you have the time to do it, how much your time is worth, whether you need it, and whether you think someone else would do a better job of it. In the end, SEO is like having a plumber living in your house – useful for the times when you need work doing, but most of the time, you can tick along nicely without them.

The best advice is: if you can do it, do it, if you can’t then don’t (sounds obvious doesn’t it). Dont believe everything an SEO company tells you, do your own research, make your own judgements and be prepared, SEO takes months or even years to get high up in google for the most competative keywords and if you are paying a high monthly fee for SEO then it might be better to consider doing some of the work yourself or employing a junior admin assistant to perform the more mundane daily tasks like link exchange administration, or writing keyword rich content to put on your website.