Backlinks bring the life blood to your website: visitors.  Without backlinks you will have to rely on paid advertising.

If you'd prefer to get 'free' traffic to your site, read on.

Back-links are links from other websites to yours and are one of the most important search engine optimisation factors. They are also critical in driving visitors to your site.

If you do not have other sites linking back to yours, your search ranking will remain in the doldrums and you won't get visitors to your site unless you have a paid campaign like Google Adwords.

Link- building can be hard work and it' a challenge figuring out what sites to target for link requests. If you are serious about SEO we'd recommend you employ a specialist SEO company who have the systems to speed up the data crunching side and can effectively pitch to high-value link prospects.

But if you want to DIY, this will get you started.

Before you start, know what keyword phrases you are targeting so you can get your anchor text right. Anchor text is the text that is linked, eg SEO Basics in this sentence.

Link building basics

1. Create great content

One of the best link building strategies is to have content that other people just have to share – and on the web, sharing means linking. Great content means you don't even have to ask for people to link to you! Quality content is something that is unique, useful and if it's entertaining, even better!

Don't decline requests by another site to link back to yours if you do have something people want to share. Apart from the fact that you can't actually stop them doing it, the only reason you wouldn't want them to do it is if they want to damage your brand in some way – in which case they won't ask you for permission!

2. Get Quality Links

Not all back links are made equal and some are not going to be of any value to you. Google will give you more credit if you get a link from a high-authority site in the same industry as you. If you are a small local chocolate maker in Wellington, a link from an Indian website about drainage systems isn't going to be of much value. But a link from Cuisine Magazine's site will be.

Try not to get listed on pages that have a lot of links to other websites on it, such as 'useful sites' pages or ones that look like big long directories. Google spots that these pages are purely for the purpose of link building and gives them little credence.

Don't get sucked into paying for links or engaging in link farms and other dodgy practises. If the links have come without you even trying, chances are they are of NO value whatsoever and could actually be damaging your search rankings. This includes link building software that 'automates' it for you.

3. Build a natural link profile

Building a 'natural' link profile means building links in such a way that Google sees it as being done without trying to scam them.

This means getting links from a variety of places, types of sites and a combination of follow, no-follow and reciprocal links. No follow links are those that have code on them to tell Google not to pass on any SEO value for that link. Many blogs and major media sites have these to stop comment spamming and junk article publishing. But a 'natural' link profile has a combination of links that theoretically don't give you a SEO boost, so include these links as well. Reciprocal links (where you link back to a site that links to you) may be less valuable but are also 'natural'.

Use your brand name in some of your back links so you also get exposure for your brand. There's nothing worse than searching for a company that you know exists and not be able to find them in Google.

Include outbound links – but don't just link to anyone. Link to other sites that have quality content somehow related to your business.

4. Identify sources for back-links

So how do you find sites that will agree to a link back to yours?

This takes time and research, but any of the following could be approached for a link, but before you ask them, ask yourself 'why would they'?. You are more likely to get a positive response if there is something in it for them.

Here's some ideas of where you can start making lists of sites to target

• Suppliers
• Customers
• People in your business network that you are friendly with
• Local business directories (many of whom offer free listings).  This is often the easiest place to get started because they want to link to you.
• Industry specific industries
• Blogs related to your industry – offer to write a guest blog or comment on an article (but don't spam!)
• 'Trusted' sites include educational (.edu), government agency sites (.govt) and organisations (.org). These back links are hard to get but possible if you have a relationship with them or are an expert in your field and can provide them with useful content.
• Article sites – write unique quality content and publish via news, PR and article sites. The low quality sites are not popular with Google who work to make them ineffective, so look for sites that publish quality articles. Don't just spin out the same article to multiple sites.
• Social media – set up your social networks and link back to the blog posts and articles on your site. Ask people to share. Answer questions on sites like Quora.
• Share your content in other forms via platforms such as Flickr (images), YouTube (video) and Slideshare (presentations)

5. Analyse the competition

Find out who the top ranking competitors are in your business niche – ie who is in the top search results for your target keywords?

Once you know who they are, work out where they get their back-links from and which ones are 'quality' links. Chances are if they link to them, they will link to you as well.

You will need some kind of back link analysis tool. These are applications that analyse a site to figure out where their back links come from. There are paid tools with many time saving features, but you can also use SEOMoz's http://www.opensiteexplorer.org/ which will give you a limited amount of links information in the free version

6. Exploit all your networks.

This includes your offline ones - people are more likely to link back to you if they know you. If you consider a back link like an endorsement, everyone in your organisation should be on the lookout for ways to get these 'endorsements' whether it is overt partnering, collaborating on content creation or encouraging content sharing through social networks.

There are many more link building strategies, and almost endless articles on how to build back link - some quite advanced. If you want to be a link-building guru, we suggest you start with the SEO industry leaders:

• SEOBook
• SEOMoz
• HubSpot
• Search Engine Land
• WordTracker