The days of free Bitcoin is gone, and most of the sites that offer free Bitcoin no longer do so when Bitcoin became expensive, now the only way to earn Bitcoin is to offer a service in some website that will in return pay u in Bitcoin,  and Bitcointalk is one of it where you can render such service, grow your account and contribute positively to the community and join a signature campaign, then you will be rewarded with some Bitcoin, and other than that you now have to purchase Bitcoin.