To print more than one image to a sheet of paper:

Open the first image.

Choose View > Sidebar.

Drag the rest of the images from the Finder to the first image’s sidebar.

Select all the images in the sidebar.
Click the first image, and then hold down the Command key as you click the others.

Choose File > Print.

Select the number of images to print on each page from the “Images per page” pop-up menu.
If you can’t see that option, click the triangle beside the Printer pop-up menu.

Choose whether each page should contain different images or multiple copies of the same image:
To print different images on a page, deselect “Print [number] copies per page.”
To print the same image multiple times on a page, select “Print [number] copies per page.”

Click Print.