Swear the affidavit
Collect your completed Affidavit (Form F30) and copies of any documents you want to attach to them and take them to a lawyer, notary public, or a clerk at the court registry. You have to swear or affirm any affidavits in front of one of these people.
Phone first to ask how much they will charge for this service, because some people charge a lot more than others.
If you're going to a lawyer or notary public, call ahead to make an appointment and to make sure that he or she can swear or affirm the document for you. Say the document is an affidavit. Make sure you tell the person that you don't need any advice.
When you go to have the Affidavit (Form F30) sworn or affirmed, take photo identification with you. The person who will swear the affidavit for you must be sure you are who you say you are. After identifying you, they will ask you if you've read the affidavit, and if you swear or affirm that the contents are true to the best of your knowledge and belief. If you answer yes, then you sign the documents and the person witnesses your signature.