I just casually have the TARDIS on my thumb!
And you can too! It’s really easy! All you need is some white nail polish, rubbing alcohol, and a picture of the TARDIS that you can print out straight from the internet!
What I did is searched ‘TARDIS Stencil’ in Google images, found one I liked, resized it to fit my nail in Word and printed it. Then I cut out the image as close as I could, painted my nail white to match the color paper I printed the image on, and while the paint was still wet and sticky, immersed the image in rubbing alcohol and pressed and held it onto my nail until the nail was dry. A couple coats of top coat and bam! TARDIS nail.
Oh and please ignore the excess paint on my skin as well as the background which is quite obviously homework that I’ve found a better use for. I was in a rush.