The easiest way I think is from faucets ... Then joining in some signature campaign in this site,
You would be pay by posting some constructive post in the threads.
Yeah faucets is the easiest but not worth the time because of the amount you will get. there are various ways but need to exert some effort to earn like in signature/facebook/twitter campaign or try trading but its not going to be easy because you need proper knowledge to be able to do it. if you have skills like editing, writing translation, excel works thats also your edge to earn in exchange of btc.