You want to create a PDF of your plot.

There are two ways to output to PDF files. One method is to open the PDF graphics device with pdf(), make the plots, then close the device with dev.off(). This method works for most graphics in R, including base graphics and grid-based graphics like those created by ggplot2 and lattice:

# width and height are in inches
pdf("myplot.pdf", width=4, height=4)

# Make plots
plot(mtcars$wt, mtcars$mpg)
print(ggplot(mtcars, aes(x=wt, y=mpg)) + geom_point())

dev.off()

If you make more than one plot, each one will go on a separate page in the PDF output. Notice that we called print() on the ggplot object to make sure that it will be output even when this code is in a script.