There are two main ways to add a signature to a PDF file:

1. Using Adobe Acrobat Reader:

   1. Open the PDF file in Adobe Acrobat Reader.
   2. Click on the “Fill & Sign” tab in the top toolbar.
   3. Click on the “Sign” button and select “Add Signature”.
   4. You can create your signature in one of three ways:
      • Type your name and select a font and style.
      • Draw your signature using your mouse or trackpad.
      • Upload an image of your signature.
   5. Once you are satisfied with your signature, click “Apply”.
   6. Place your signature on the PDF file by dragging and dropping it to the desired location.
   7. Click “Save” to save your changes.

2. Using an online PDF signature service:

   There are many online PDF signature services that you can use to add a signature to a PDF file. Some popular options include:

    * DocuSign
    * SignNow
    * Adobe Sign
   

   To use an online PDF signature service, simply upload the PDF file and follow the instructions on the website to add your signature.

Once you have added your signature to the PDF file, you can download it and share it with others.