The purpose of notarization is to confirm that the signature on the document is real. You must take your document to be notarized without a signature and in front of the Notary Republic sign and date the document. The Notary will then stamp it thus concluding the process. Notaries are generally located in banks, lawyers offices etc.
Please note, documents that are originals issued from the State, County, City or Court do not need to be authenticated such as certified copies of marriage certificates, birth/death certificates, good standing etc.
A. Notary Certification
Some states require that the notarized documents are also validated by the County Clerk in the notary’s county. This is to ensure that the Notary is a legitimate, registered Notary in that county. Call your Secretary of State’s office and ask if this is necessary, if so, simply take the documents with the Notary’s stamp to a county courthouse in the same county as the Notary. They will issue a different stamp verifying that the Notary is registered.
The notarized documents must then be authenticated separately by the Secretary of State in the state of which the notary republic is registered.
For instance if your documents are notarized in IL you must get them authenticated by the Secretary of State in IL.
B. Notary Testimony
A notary testimony is sometimes needed on documents to verify that the notary did indeed do their job on the specific date as reflected on the issuance of the document. For example, a document written on 7/12/2015, would need have a notary testimony also on that same date.
Here is an example of what a testimony can look like:
On this, the____day of __, 20, before me, a notary public, the undersigned officer, personally appeared____, known to me (or satisfactorily proven) to be the person whose name is subscribed to the within instrument, and acknowledged that he executed the same for the purposes therein contained.
In witness hereof, I hereunto set my hand and official seal. (notary then signs and dates)
Such instances where a document would need a testimony could be a company letter, giving authority to a lawyer or representative to submit on behalf of the company. Generally speaking, an original birth certificate would not need such a statement.