You can cut place cards out by hand with a sharp pair of scissors if you are very steady. But my preferred way of cutting out place cards is with a paper cutter guillotine trimmer, like this one from Swingline. I can measure each one out so that it comes out precisely the right size and know each cut I make is going to be symmetrical and clean. This is the single best way to cut out place cards, especially if you're cutting a large quantity.