Print the PDF. Fold each page down the middle along the dotted vertical line and cut the solid horizontal lines.

If your printer has a special "duplex" option, you can use it to automatically print double-sided. However for most printers, you need to:

1. Print the "odd-numbered" pages first
2. Feed the printed pages back into the printer
3. Print the "even-numbered" pages

If your printer prints pages face up, you may need to tell your printer to reverse the order when printing the even-numbered pages.