Empty tin cans
Spray paint of choice
Mechanical pencil with eraser end
White acrylic paint
I used Rust-Oleum spray paint in satin aqua. I got this at Walmart for $3.77 This thing has lasted me a while...I have spray painted over 10 cans and bottles, and there's still more remaining.
Make sure to test the nozzle on a rough surface if it is your first time using spray paint. Spraying a few times makes for smoother spraying.