Start by inputing DC losses in Section 1, these are the basic loads that will be drawn from the battery.
If you will not use an Inverter (to produce AC power for TV's and microwave or air conditioner) there is no need to fill out Sections 2. If you will be using an inverter, complete Section 2.
After you have input the losses, select your location in Section 3 and enter the number of solar panels and a solar gain value will be calculated.
Section 4 provides a summary of losses and gains and some suggestions.