Mac Preview Signatures

Another nice feature of the Mac Preview app is being able to create signatures on the fly using a trackpad or camera, and then adding and sizing them to a document.  For the trackpad, you use your finger or a soft-tipped stylus, and for the camera you sign a blank, white piece of paper and place it level with a blue line in the camera window.  You also use reuse signatures you've previously created by simply clicking on it, as shown below.

https://support.apple.com/guide/preview/fill-out-and-sign-pdf-forms-prvw35725/mac