Easy way is to use paper template and just fill spots with black marker pen, but I also saw people started making interesting plastic backup plates with tamper protection.
They are obviously not as durable as stainless steel or titanium plates, but they are good option when traveling and going in airports scanners.
There are cons and pros for everything.
Yeah, it fits my plot, only instead of a paper template I intend to use the-laser-printer-transparency-film with the preliminary printed compact SeedQR-template like this
After mapping (by the fibre-tip pen with permanent ink ) this template with Compact SeedQR image relevant to my SEED, I place it on steel plate and hummer it with a punching ttip.