Making an A5 book from a pdf-file

Here's how to create an A5 book from a pdf file. This procedure can be done by creating a script that runs through the needed steps automatically. I'll see if I will do that later. But here is the necessary steps to do this manually.

The mission is to print a folder on A4 paper, and fold it into a book.

1. Calculate:  (number of pages \ 4) + 1 = Sheets  (This is needed as the -s parameter in the psbook-command. If the original document has 9 pages then we need to use the following calculation: (9 \ 4)+1 = 2 + 1 = 3)  2 sheets will hold 8 pages which is one page less than the document. 3 sheets will hold 12 pages and is more than the document.
2. Convert the original file to a .ps-file:  pdftops original.pdf new_original.ps
3. Create the pages in the book: psbook -s3 new_original.ps new_original_book.ps   (Refer to step 1 for info about -s3 parameter)
4. Reorder the pages using psnup: psnup -l -n2 new_original_book.ps new_original_folder.ps  (Parameter -l is to print in landscape, and -n2 is to place 2 pages on each page.)
5. Convert back to pdf-format: ps2pdf new_original_folder.ps folder.pdf
6. Remove temporary files: rm new_original_*

After we have printed the book; the pages should come sequentially as in all books. Fold, staple and deliever you brochure/folder. If the original document is more than 4-5 pages we might want to cut a little in front of the book after we have folded it.