This article and video will show Notaries to fill out each part of a notarial certificate, and common mistakes to avoid. It is recommended that you complete the Attorney Registration Information section of the form online and then download your form to physically sign.Always be sure to follow your state rules if asked to notarize a signature on a power of attorney document. Failure to fill out this section will not affect the validity of the certificate. Even California law says that legally performed notarizations from out of state are perfectly acceptable in California. Sign and Stamp the Document: Sign the notarial certificate and apply the notary seal. Under California law, the notary is not allowed to choose which kind of notarial certificate you should use. Description of Original Power of Attorney.