How to create PDF-files
A resolution of 150 dpi is sufficient for your PDF files.
Adobe Acrobat Professional
This programme is the most convenient possibility to create and edit PDF-files. In case you have access to this programme, it is most recommendable to use it.
Microsoft Word and Libre Office
Since Version 2010, Microsoft Office supports the export in PDF-files, if you are using Version 2007, you can use this plugin. All versions
of LibreOffice are able to export in PDF-files.
PDF-programmes as virtual printers
Using free ware programmes like PdfCreator or freePDF, you can convert all kinds of documents to PDF-files via the printing function.