This summary is not the rule. The rule text controls.
If you need to submit a sworn statement to the court, you don't always have to use a formal affidavit. Instead, you can write and sign a declaration, which is a simpler option that doesn't require a notary.
To make your declaration valid, you need to state in writing that what you're saying is true, sign it, and date it. The rule gives you a basic format to follow: you write your name, say you declare under penalty of law that everything you're stating is true and correct, then add the date and your signature.
This option makes things easier for people who need to submit statements to the court. You skip the step of finding a notary to witness your signature, but you still take on the same legal responsibility to tell the truth. If you sign a declaration knowing that something in it is false, you can face legal penalties just as you would with a sworn affidavit.