I used to do this alot when I was younger. I so much wanted to be like gambit from x-men. ahh sweet youth.
I found to begin with, using heavier cards like I.D., library cards and such worked better to begin with. I started out trying to throw them level, but soon discovered that throwing them perpindicular to the ground was more accurate, and they still leveled out pretty quickly.
keep in mind I haven't done this for quite some time, so my advise might sterr you in a wrong direction.
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you can't have a war against terrorism because war IS terrorism.
it's not about worshipping fire. its about making the fire want to worship you.