I was using the texture for a fish model for a mod, but I tried over and over and it wouldn't stop saying ERROR. But here you are, they may not be fish mobs in the game, but there is paper minecraft fish.
Cut out all pieces (on the fins are an extra pixel long, so cut that)
fold all pieces. WARNING: the tail might be tricky.
glue the pieces.
glue the individual pieces together (B on B, A on A) the lines are the spots for the fins.
Click on the papercraft design image.
Make sure it has not been resized by your browser (you might need to click the image again).
Print using your browser's Print function.