Formatting figures

The two-step pattern hands you a bare plot on purpose: content first, appearance second. This part is the second half. The constructor decided what the figure shows; here you decide how it looks, and you do it with ordinary ggplot2 layers added on top.

The split pays off because the same plot serves several audiences. One object becomes a greyscale manuscript figure, a high-contrast poster panel, or a slide, by changing only what you add after plot(). The chapters cover the pieces in turn: annotation and axis formatting, the house themes, colour scales, and legends. Read them as a toolbox, not a sequence – pull the one you need when a figure is almost right but not quite.