Click on the office button on the top left of your screen, then click on save as. From there, you should find (PDF). It is right under (file name). Once you have selected (PDF), click save. Make sure you know where you saved it. It may automaticly pop up when you have completed the process.
Or you could go to http://www.online-convert.com/
All you need to do is click on the websight above, then click on document converter. There is a varity of selections to chose from and yes, there is a PDF format in there.
Hope this helps.