Height of the drawer case, number of drawers, width and height of individual drawers
A cardboard mock-up is a very important step in my opinion, as it serves to both provide a visual image of the drawer case and to point out any possible subtle issues with the layout. The drawer case is set back from the edge of the main case to allow for drawer handles and a little extra for the door stops. The drawers can be removed and individually placed on the top of the drawer case for better viewing. I debated whether to overlay the horizontal drawer dividers with the door fronts, but since all the wood is uniform and of the same species ( cherry), I would have the horizontal dividers visible. The components of the drawer case are for the most part dadoed and rabbeted together and the horizontal dividers each slide in between two grooves. The center vertical divider will be permanently attached to the drawer case. The rabbeted sides will also have a couple of dowels in each of four edges for reinforcement.
Since the cardboard mock-up is sized exactly to scale, I have the benefit of using it to size the components of the drawer case for milling and dimensioning. At this point, the boards used for the drawer case are sawn and they are allowed to stabilize before any further processing. This is to remove any inner stresses in the wood.
The individual drawers will have dovetailed drawer fronts and rabbeted backs and the bottom panel will be floating in a small groove on all four sides of the drawer.