I’ve found I like writing in Japanese. If I have to learn vocabulary I may as well (try to) learn the kanji that goes with it. Certainly if I’m writing I’ll use kanji if I can. I might not remember them to write afterwards but I can usually recognise them again if I’m reading.
Some really good writing surfaces are bananas and wet sand.
For advanced credit you can write on people!
(see “The Pillow Book” directed by Peter Greenaway, 1991)
But anything as permanent as a tattoo is a very bad and stupid idea.
For reasons why having something permanently written on your body in a language you probably don’t understand, these pranks about Chinese tattoos are good illustrations.