How to earn bitcoins safely, without scams

I ask: How do I know which site is reliable, where to invest, not to waste time and not be ripped off?   

My answer: Simple during this July, was given the Halving of bitcoin, which marked a before and after, well, every place that has remained standing after that event, we can continue to work in they even put our trust not 100%. 

On the other hand what if I'm sure at 100% is that all mining site (cloud mining) that opened or will open after the event in question, since you already have fraudulent purposes while its authenticity is proven, since it is known by you, the halving caused the reduction of the reward received miners by adding a new block to each principal. That is why we think the mining sites in the cloud remained and still operating to date, managed to endure and still maintain profitability with the equipment available to them. 

I recommend working at these sites: bit.ly/1X6iUEq 

All bore the halving and time consuming mining providing the service. Do you share that opinion can? ... That new site was opened and already tends to be fraud, discuss it below.