In the Page Setup tab you can choose several options concerning the layout or the paper. Choose how many sheets shall appear on one piece of paper, about two-sided printing, limit the printed pages by even or odd page numbers or the scale in the layout section. Select the paper type (e.g. preprinted) and the paper source and output tray in the paper section.
The preview in the lower part of the tab gives you a small hint of how your printed document will look like.