Spare 50% of that, re-invest the other half. I do that with all of my monthly income, since I don't pay for the food, water, electricity, etc. My only expenses are what I eat/drink at school, and I make more than enough for that.
Working great for me. I get to have some money on the side to buy myself something nice when I get more, and I get some cash to re-invest and possibly make even more.