Put a plus or minus sign in front of each of sqrt(1), sqrt(2), ..., sqrt(50). How do you make the total as close to zero as possible, and roughly how small can it get?

Take the numbers sqrt(n) for n = 1, 2, ..., 50 and put a plus or minus sign in front of each. How should the signs be chosen to make the total as close to zero as possible, and roughly how small can it be made? An exact or rigorous answer is not required.