Hi all, 
I am ready to design a booklet with 12 pages.
I would like to ask how to arrange pages in the files?
I think it is better to have 6 file with two pages. As follows:
first file: page 12 – page 1
second file: 2 page – page 11
...
What would you advise me?
Hey ArtTiculas,
The best thing for you to do (if using InDesign) would be to set up the entire file like normal – don’t worry about how the different pages will line up once it’s made into a booklet. The user of your file will be able to navigate the file much better, and you can include in the instructions file how to export as a booklet for print (file > print booklet (adjust specs in dialog box that would appear)). Hope this helps!
Thanks for the help! 
And when I use photoshop how to arrange?
That’s a tough call, as InDesign is meant for layout/booklet design more so than Photoshop. If you decide to use Photoshop, I think the best way not to confuse the buyer would be to save each page separately, where they could then place those image files into InDesign to print or create the correctly arranged booklet.
Thank you very much Teela!!! Good luck!!! 
No problem! Good luck to you!
I’m just designing a menu for restaurant with several pages. I also use PS. I decided to include it all in one file but make one folder for each page. This way the customer can just hide/show different folders and even combine different pages. I name them:
Front page 1 page 2 page 3 etc Back
Of course you have to make sure that the page number coincides With the correct side of the layout, i.e. page 1 must be the left half of your layout, page 2 must be the right half, front must be the right half, back must be the left half … At least with conventional folding.
Cheers
Chris
Thank you very much for useful info 
Cheers
