For gear mesh I use 3 methods. First I eyeball it and make sure there is a small space between the two gears, then I hold one gear and rock the other back and forth. You shoul get a bit of movement out of it. Then if I'm still not sure I'll do the paper trick. Gear meshing seems like a simple thing, but it actually takes a while to get right most of the time. Usually now I just set the mesh by eye and feel, and I don't even need the paper. In your case use the paper first then look at it, and then rock the gears to see what a good mesh feels like.