you can actively participate in several bounty campaigns. this guarantees you a good profit, especially if the project goes to the exchange, and your rewards can increase by several hundred percent in price. Also, this earnings can be obtained with the mining of bitcoins, but this is an expensive investment, and the period of occupancy will be quite significant, before you can earn such a sum in a month. Another way is trading. Your earnings will consist in the difference in the growth rate of potential crypto currency: buy cheaper, sell more.