The Blank Gun certification documents are whatsapped to you and include the card, all of your details as well as a copy of the Law regarding Blank guns.
You need to print 2 copies of this document. The first copy can be kept as is, but the second copy is cut up to make the card. It is preferable if you laminate the card. If you do not have a laminator, you can take it to any Postnet or stationery shop and ask them to do it for you.
Please keep those documents with the gun at all times.
Although the law does not require that you have these, the local SAPS are asking all owners of blank guns for the card and if you do not have it, you stand the risk of your gun getting confiscated.