If you need to sign a form or other document in OS X, look no further than Apple’s Preview application. Letters, contracts, and other documents are progressively migrating to digital media as PDFs; however, you may still be required to stamp them with a personal signature. One approach for this is to print out the forms, sign them, and then scan them back in to your system; however, another approach is to paste an image of your signature on the document.

To do this, you can scan your signature and then crop it, followed by pasting it or otherwise combining it with your PDF, but this can be cumbersome, especially since the scanned image might not have transparencies around the signature, resulting in obscuring part of the PDF. To overcome this, you can use the signature feature in OS X’s Preview application, to save your signature and then neatly embed it into any PDF.

First, sign your name on any sheet of white paper, and then do the following:

Open a PDF in Preview Press Shift-Command-A to display the annotation tools Click the signature tool, and choose the option to create a new signature using your Mac’s FaceTime camera Hold your signed paper up to the camera and align the signature with the blue line on the display

When you do this, you should see a captured image of your signature appear in the preview window, and you can then click the button to accept the signature and save it for use after Preview quits.

With the signature saved, you can then select it from the signatures annotation tool and click anywhere in your PDF to place it. You can then move and resize it accordingly, and it can then be saved or printed with your PDF.

Preview will not only save your signature in this manner, but will also allow you to make multiple signatures and keep track of when each was created and last used. This can be convenient for allowing some variety in your signatures, and update it as it changes over the years.