Update: The base has been made higher resolution than shown in the picture

All parts except for the shell can be printed without supports.
I used 1.5-2.0mm layerheight depending on the overall printtime.
I also used a little bit of glue while inserting the balls but this isn't necessary.
I would recommended to use pliers when inserthing the balls because it can be quite challenging to do it with your fingers.
I added bevels to most parts to make them easier to assemble.

Make sure to print “Snowman-button” 5 times, “ball-4mm” 8 times and “Ball-4mm” 29 times.