After trying this technique with couple of most competitive keywords I would like to share this technique with all the people who really want to boost their site rankings and are willing to accept the costs involved in it. 1) Register 10 to 50 keyword rich domains. 2) Host them on different servers with unique IPs. (I prefer Linux Servers) 3) Install Wordpress on all the sites. 4) Create 10 to 50 very informative and useful articles and post on these sites. Make sure you don't post the same article on multiple sites or use spinned article. 5) Wait for 1 week. (You will see great results in rankings) 6) If you want to improve the rankings more, just go on adding more articles to your 10 to 50 sites and create backlinks to these sites using relevant forums. Enjoy your rankings!
This technique will no doubt give you results, but its pretty costly. Isn't there any other way which is cost effective because clients does hesitate to spend more money and its get difficult for SEOs to make them understand.
I agree with the last post. If you're doing SEO for the first time, start with achievable goals first so you can test the waters and see how things work in the SEO space. We can't control everything but it helps to do the right thing all the time.
In theory you can use free domains or subdomains, in part or entirely...just pick with reason and avoid unreliable providers, ad supported ones are fine for the purpose.