it's all depend on your electricity, with free electricity you can earn about 0.36 with the best miner on the market(antimer s5)
and this with free electricity...
i would suggest to join a campaign instead, you can actually do 1 btc month with it
would like to know more about that, and if i am eligible
you mean signature campaign?
you need first to rise your activity to senior member at least if you want to earn a serious income, otherwise there are also signature campaigns for newbies/jr member/ecc..., but you can't make 1 btc a month with those