In this document I write about how to edit a PDF file using the built-in OS X preview app. But sometimes you need to add your signature to a PDF document. Well here is some good news – you can also sign a document right from within the preview app. Thanks to Bryson who pointed this out to me!

1. Firstly click the pen symbol as if you were going to edit the PDF file.

2. Then click the ‘create signature’ button.

3. Sign using the track pad or camera.

If you select “trackpad” you will be able to use the trackpad on your MacBook to sign your signature and the app will record your signature and keep it in preview for signing future PDFs.

If you select “Camera” you just need to sign your signature on a piece of paper in panel pencil and then hold it up in front of your computer’s camera. Preview will automatically adjust your signature and scan it.

Now you can just select your signature and preview will insert it into the PDF document when you need it.

Your signature will automatically be stored in preview so that you can use it in the future, but if you want it deleted for security purposes you can simply click on the cross on the right-hand side of your signature and it will delete it.