Qcad howto ?

Hi Anyone here using qcad ? As one who'd never done any serious cad work, I'm looking for a howto - or best practice description - for getting started drawing a building with qcad. E.g. will I begin with the whole ground as the first layer, draw the outer walls of the building as the next, or is there a better approach? I hope that someone can point me to some introduction material for this kind of qcad use. Thanks in advance