I used acrylic paints, which are pretty much completely permanent.
For the water drops (and everything else actually) I used stencils that I made myself and cut out with an exacto knife. All the little details like the shading on the water drops and such, I just used a suuuper teeny brush and blended paints when needed.
I got the original tutorial from Soompi
here. (Scroll down a bit, first someone posted one that's kinda small but if you keep scrolling, there's another post with a huge one.) The steps I posted above I had taken from the tutorial and just edited on Photoshop so I could print it out and follow it. :]
Thanks for the nice comments guys! ^^