If you are using OpenOffice it is very easy to create documents there is an option in the File menu ‘Export as PDF’.For other applications, you will need to do the following procedure

We need to install cups-pdf this software is designed to produce PDF files in a heterogeneous network by providing a PDF printer on the central fileserver. It is available under the GPL and is packaged for many different distributions or can be built directly out of the source files.

Install cups-pdf

sudo apt-get install cups-pdf

You need to chnage the following file permissions

sudo chmod +s /usr/lib/cups/backend/cups-pdf

Configure CUPS for the PDF printer.

- Select SYSTEM > ADMINISTRATION > PRINTERS > NEW PRINTER
- Select LOCAL PRINTER
- Use detected printer: PDF PRINTER
- Select Print Driver:
- Manufacturer: Generic
- Model: Postscript Color Printer
- Name: postscript-color-printer-rev3b
- Click APPLY

When printing from any application, select the newly created postscript-color-printer-rev3b printer to generate PDF files.

Output files are stored in your home directory under /PDF subirectory.

To change the default location of the PDF output

Edit the /etc/cups/cups-pdf.conf file

gksudo gedit /etc/cups/cups-pdf.conf

look for

Out ${HOME}/PDF

and change to something like below

Out ${HOME}/my_print_to_pdf_folder

and restart

sudo /etc/init.d/cupsys restart