AFAIK, we don’t provide on yet. So the fastest way would be to go to File->Document Setup, change your paper size and save. Then go to a page, select all, and scale to a ratio you want: if you want to keep the current aspect ratio, hold the shift key as you rescale. Note the final aspect ratio that look best, in the lower right hand Measurements box. Then on each page, you can Select All, start dragging, and type the scale size you want for exact scaling. For example, if it’s a simple 2x scaling, select all, start dragging (lower right grip), then type 2,2 Enter.
If you want larger text as well, select all, and adjust the font size up in the font inspector.
By the way, shift will preserve aspect ratio on resizing, and command / alt will scale from the center of your selection.