The stencil I used is a number stencil and is plastic. I tried using Distress Stains at first, because I thought the application would be easy. It was...too easy. It leaked and smeared and looked like this.
This shows the pounced ink on the left and pounced acrylic paint on the right. Not bad, but still a bit smeary where I didn't pounce up and down and swiped instead with the finger dauber.
I had to try Stickles, as they are my favorite thing in the world...y'know besides the kids and husband. I used a lot of Stickles and just smeared it in with a finger. It's spotty coverage and you use a lot, but it's a cool effect.
The best effect was using the gel medium with acrylic paint imo. I used an old gift card to spread the gel medium first and then spread some paint on top. It's thick but not gloppy and came out a crisp image.
I tried just gel medium on the left, spray ink at the top and glitter paint on the right. You can see that my stencil was still a bit blue because the gold paint has some blue tinge to it.
I liked using the gel medium with paint and then stain too. The stain colored the paint a different blue but was thick enough with the gel and acrylic paint not to seep through the edges.
Last caveat: Don't touch the gel to see if it's dry yet. It's thick and takes awhile to set. Mine took a half-hour or more. See the dent in the 9 where I checked too early? :)
So try fooling around with the stencil and different media. If you want crisp and lovely, try the gel medium with acrylic paint as a second layer (while the gel is wet and the stencil is still taped down.) But, be prepared to spend a bit of time while you play around. I thought it'd go fast, but I kept wanting to try different things with it while it was still out. I tried some different papers too. I didn't see much difference, except that the thin paper buckles with too much media.
Oh, and clean the stencil periodically through the process. If you use Stickles, remember that's a glue. You can wash it in a regular sink and dry with a paper towel. Pat and don't rub the stencil, so you don't bend the pieces.
Have fun! Hope this helps!