Digital signature is the alternative way of signing documents in era of electronic exchange of documents. One of the most prevalent types of these documents are PDF files. There are professional tools on the market that one can use, by spending certain amount of cash to achieve digitally signing of these PDF files. There are also limited number of software publicly available by creative commons in form of open and free software.
Steps
Download PDF utility from Messiah's "codes for us" blogspot.
You should decide for visibility of the signature and if it is a new signature on the document or an added signature by checking the radio-buttons available.
One should have "PKCS#12," that is, a PFX key-pair certification available in the directory or somewhere on his desktop; its "password" should be entered into the required field.
You can decide where on the document put your digital signature, by entering its coordinates manually in the coordinates field or by clicking on the "Get Mouse" button to open a scaled replica of the page of your document. Take the cursor and create a rectangle as the place-holder for your digital signature.
At the end click on the "Sign It!" button. Your signed file comes with a new name in the directory to keep your original file untouched. You can rename it to whatever name you like.
