This is a quick explanation of how to make prototype playing cards the easy way. It’s so easy in fact that the pictures alone tell the story but I’ll embellish it none the less.
Why not just use card stock? It's not that much more expensive that copy paper, and that way you didn't need to worry about backing it.
This is more complex than what I end up doing. What you will need:
1) Software that can freely rotate and print your cards 90 degrees. And a printer.
2) Decent paper cutter.
3) Card backing (MtG cards, playing cards, or even colored or white 110 lb cardstock cut into 3.5x2.5 inch cards)
4) Penny sleeves.
5) 20 lb paper.
You can print 10 3.5x2.5 playing cards on a standard sheet of U.S. Letter-sized paper. You just don't have any margins.
Screw the margins! Incorporate them into how you design your cards (and make them appropriate for your printer). Even with a printer with bad margins (I had 8.0x10.4167 inches on my old printer), you can put the worst margin on the bottom.
USE THE EDGES OF THE PAPER to your advantage - they are more accurately straight than you can manage on your own with scissors or a paper cutter, so there's no reason not to push your cards as far to the margin as possible.
Similarly, don't draw boundaries for your cards. Just use the ruler on the paper cutter to properly cut your cards - the inaccuracy of the paper cutter is nullified when you use decent margins (mine are approximately 1/6 of an inch, based on my printer's margins), and adding cutting lines only makes it look worse.
We print on the 110 card stock then cut them and place them in sleeves. We cut off the margins on the outside, then use the paper guide to cut 3.5 inches every time, then cut the 2.5 inch side after placing the guide to that measurement. You get very consistent cards that work well and once in the sleeve almost have the same weight as a playing card.If we are experimenting with card back design we work with clear sleeves, otherwise the cheapest color backs will be mostly opaque when combined with the 110 pound paper.
Sounds like you are doing the same thing to me.
Print, cut, & sleeve with backing card.
I’m just not exact in doing the cutting because I don't feel it matters in a prototype that will change. The cards shown are the territory cards for Eden 1157B, it has gone through numerous modification and is bound to see more before it's done.
In this case there are 54 cards in the set. This is a multiple of 9; 6 pages so no need to rotate anything. Having 5 pages of 10 cards and 1 with 4 cards doesn’t save time or paper.
When I do need to get more per sheet I don't rotate the cards I set the page to landscape. Has the same effect.
We create our "cards" through Microsoft Office Word 2007 and slip them in front of various cards to represent different card types; MTG for creatures, VS System for Tactics, and Pokemon cards for Structures, Territories, and Strongholds.