First of all, choosing a freelancer is something that should be taken just as seriously as any business decision. Before you begin, you should already have well thought-out steps and procedures and be committed to following them.
If you don't have your own successful methods or if you have failed in the past, try this:
Carefully plan and write out a job post. Read other blog entries here to see how it should be done - Attract the Best Freelancers
Make your post on Elance, Odesk, Guru and throw in about 2 more freelance sites of your own choosing.
Once the proposals and applications are coming in, you will need to use a predetermined criteria and have a set of expectations by which to judge and distinguish them.
1st - First of all, you will be looking at the application that they submitted. You will want to know if it is just a form application that they have spammed to dozens of other clients, or if it is well thought out and personalized just for you and your project.
2nd - Next, you will want to know if they followed any instructions that you might have given in your job post (such as stating a keyword, or giving a quote on their price, or any other request that you would have made).
3rd - After checking over the proposal, you will then want to check out the freelancer who submitted it. You can do this by looking at the freelance workers' profile and stats. I highly recommend the use of analytic tools in order to help rank individual contractors with a scoring system. I use such a tool and can provide you with it as well. Elance Contractor Analysis and Selection
This is a tool particularly designed to sort through Elance contractors so that you don't have to. The most sensible thing that one can do is use an analytic tool to rank freelance contractors from best to worse based on their statistics. After that you can use your judgement and take into consideration any special needs that you might have for a particular project. By using tools along with human judgement, you will quickly and easily work your way down any list of freelance contractors.
If you followed the 5 golden rules of submitting a proposal, you should have attracted several suitable contractors from each of the 5 freelance websites you posted on.
State Your Needs Clearly
(Rules 2-5 will be posted to this blog later, come back soon to see them)
Now, you will start the hiring process.
1st phase of Screening - you will judge the applications on each site one at a time and exclude the undesirable freelance contractors. This means that you will generally have about 10 or 15 well qualified freelancers to make your choice.
2nd Phase of Screening - you should select at least one from each freelance website and hire each of them part-time. There are several important steps to take in doing this correctly. Read my Using the Right Hiring Technique post for more details.
3rd Phase of Screening - you will want to work with you part-time hires for a short time and observe who has the best potential. You will then hire this person full-time. Read my Using the Right Hiring Technique post for more details.