So what are you? A night owl, who stays up late to be productive in the quiet hours of the night? Or an early bird, who rises with the sun and finds their productive hours before everyone else is stirring?
I ask this because you will probably need to find out which one - and I say ONE for a reason- and try to implement your working hours around your body's clock. While we can be productive during the daytime, many of us are bombarded with "real life" during those hours - phones ringing, kids having to go places, assignments, doctor appointments, errands - and find that we can lose great chunks of time to these seemingly mundane tasks. If we try to work only during these hours, we may lose a lot of "productivity."
Instead, if you know you can block of two or three hours in the evening (or morning) to dedicate solely to your production, you will be that much more efficient!
A word of caution: Don't do both. Burning the candle at both ends is physically and mentally debilitating. While it may work in the short term, it's detrimental to health, well-being, and possibly career.
Don't look for me to be an early bird - if the sun isn't up, neither am I. Coffee is required for me to begin moving in the morning. However, I am quite often up past midnight. I seem to do my best work in the evenings. (Maybe it's because I'm married to an early bird, and he's out cold by 10p?)
Use your time wisely and efficiently.