I use cardboard that is taped down to the crumb tray. Cut out the cardboard for the cards and then plop in the material you want to attack.
How familiar are you with vector design programs like Inkscape?
Give me the dimensions of your cards and I’ll make you a file that you can place your information in. Cut the outlines. Then put in the cards. Then rinse and repeat?.How many do you want to do at a time? I’ve done lots of designs like this. I’ll help. Something like this?