These are a couple of ways to get free backlinks for your website.

1.Forum Signatures

You can join forums and write your website URL in your signature Anyway be careful,not every forum accepts links in signatures so read the rules of a forum before putting your website URL in your signature

2.Add your site to Free Web Directories

Web Directories are the easiest way to get free backlinks.The only thing you have to do is to add your site to the correct category For fast form filling you can use a tool called InFormEnter

3.Writing Articles

You can also write and submit articles. The terms of someone using your material includes full credit of authorship including a link back to your own site.

Writing is not for everyone and may be more time-consuming than the other tips mentioned here. The benefit of getting your work on someone else’s site should drive traffic to you and enhance your reputation as an expert.

Publish on quality sites. Avoid scraper sites based on Adsense and affiliate revenue. Be as on-topic as possible.

4.Blog & Social Media

Create a blog of your own.What better way would you have to present your good content to potential linkers than posting it in your blog? It is important that you create a blog as a part of your domain, i.e, if your domain is http://www.example.com/, you can have a blog as http://www.example.com/blog . This helps to transfer the power of the free back links that you get in your blog to the main domain also.

Create good content on your blog and submit them to the social media websites like Digg, Del.icio.us, Reddit etc. If your content is really good, you are sure to get a host of Free back links.

5.Website Review

There are various websites and forums that conducts review of website/product/services. Submit your website to these and with each review you are sure to get at least one free back link. ( Drawback: if your product/service quality is bad you might get some negative review which in turn can affect your business)