How To Sign a PDF Document on Your Mac

Open your pdf document that needs to be signed in Preview.
Click TOOLS, ANNOTATE and then at the bottom SIGNATURES.
Here you can either sign a signature on a white piece of paper and hold it in front of the camera (press camera option) or you can sign on the trackpad option - this can take some practice to get your signature perfect. Once you save your signature it can be inserted into the document.