Thanks everyone!
Hahaha. So... for the stencil, I actually didn't have time to run to the store to get some stencil sheets or anything, since I was actually supposed to be done with my samples before... well, today for the meeting. I kinda improvised. The only thing I had that would work was tracing paper, so that was a one time use thing. I had to hold the paper down at some points, so I had paint all over the fingers of my left hand. Normally, though, I'd be cheap and use a transparency (mostly airbrushing), or the stencil blanks. I heard the Dura-lar overlay paper works great, but I don't have a Hobby Lobby store near me, and I don't want to pay a crazy shipping price for it.
For stencils, what's really important is to not use a normal paint brush, but rather, sponges or a stenciling brush, and to apply the paint when it's just barely moist and not wet (which meant dabbing the sponge on the paper plate until all the excess paint is off), else it seeps under the stencil (even if I had used a plastic one).