Page Imposition

I’ve just created two pages, 9.5 x 12 inches, which I would like to print on a single page 12 x 19 inches. How do I get the pages to lie side by side. i.e. the first page on the left, second on the right?

In engrave mode, right-click on the first page icon (Pages, upper right) and select insert page number change… change page 1 to be page no. 2…

Ah, that’s what I was trying to find. Thank you!