From personal experience, after investing time in learning and applying and bidding and experimenting profile and doing test one after another in Odesk lead me to get my first task. Don't expect to get a high paid task on your first job. Your task is to finish the job and get feedback score to have a ground that would reflect your skills.
You can follow my tips. Its not necessary that every tip will work for everyone, but it is working for me.
Tip #1 :
|Tip #1 Uncheck 'No Hires' checkbox to avoid Fake job post in search result|
If you have any questions, comment below.