Pretty simple. The bridge has the helm, navigation, and engineering stations. Twin double bunks to hold the three crew and yourself. The fuel cell looks small, but it's adequate for over a week of continuous use, even at TL1. The brown area to the right of the fuel cell is the cargo bay, which holds more than enough to get a moon base or other colony up and running.
Please note that this design is only one level high. You could make it taller, of course, but as I said this was designed for ease of docking. Also, make sure to change the engine module to a rocket motor, instead of a gravity drive. This is important if you do not yet have access to eludium, but if you do than I don't think it matters much.
