If you have nothing to do right now, become an expert at throwing cards. When you have learned to throw cards (after a lot of practice), you can train as in the videos below. Good luck!
Learn How to Throw Cards with Mark Rober | Behind the Scenes | Rick Smith Jr.
Card Throwing Trick Shots | Dude Perfect
Card Throwing Tutorial | Accuracy & Power | Rick Smith Jr.
Now just practice and practice, and you will be able to throw cards with great precision.