If you have PowerPoint 2010 or more recent, you can save your PowerPoint file as a PDF file with 3 slides per page and note lines to the right.
For PowerPoint 2016/2013:
Open your PowerPoint and click on File.
Click on Export, choose Create PDF/XPS Document, then click on the box that says Create PDF/XPS.
Make sure Save as type: says PDF (*.pdf), then click on Options...
Under Publish options, change the Publish what: drop-down to Handouts, and then change Slides per page to 3. If your slides have a light background, you may also wish to check the box for Frame slides to add a thin border around your slides.
Click on OK.
Make sure the File name is the way you want it and select the location where you want to save the PDF file.
Check the box for Open file after publishing if you want to view the finished PDF file immediately after it's created.
Click Publish. That's it!
For PowerPoint 2010, you will first need to download and install a free PDF maker such as CutePDF Writer. (Note: this isn't needed if you have Adobe Acrobat Pro installed on your computer.)
Open your PowerPoint and click on File, then select Print.
Under Printer, choose CutePDF Writer (or other PDF creator) in the dropdown menu.
Under Settings, choose 3 slides under Handouts. On this same dropdown menu, you may wish to check the box for Frame Slides to add a thin border around your slides. Checking the box for Scale to Fit Paper will make the slides as big as possible.
Click the square Print "button" at the top of the page.
On the Save As pop-up box, choose the location where you would like to save your new PDF file, then click Save.
Go to your new file and open it to be sure it looks the way you wanted, and you're done!