Save your file either to your computer, or to an online service like SkyDrive. Then find out how to share it with others, even if they have an older version.
Use PDF or XPS format to help preserve the formatting in your file or to share the file with other people.
Save your PowerPoint 2013 presentations to SkyDrive.
You can share and reuse individual PowerPoint slides by storing them in a Slide Library on a server running Office SharePoint Server 2007 or Microsoft SharePoint Server 2010. You
Create and share a presentation with other people on the web - and they can access it using any device, from anywhere.