This is a (so far) printable Enderman made in OpenSCAD. I wrote it looking at screenshots of Minecraft.

Printed at 133% scale, it can hold calibration cubes.

(though the cube may weight so much and the Enderman falls on its face)

It is printed upside down, and feet are made wider so it can stand.

It needs no support material, and if you have your printer carefully tuned, there would be no problem.

The mob itself is so skinny so printing it may be challenging.

EDIT: Enderman_holding feet are made bigger, so it can stand when holding nothing (at least)

EDIT (2): Idle Enderman's feet made bigger like the Enderman_Holding, and put in some Enderman 5.3 files.

Slice and Print. That's it, but...

You may want to scale it bigger, the actual model is so small (arms' width 3mm) and you may want to make it BIG or to make it SLOW.

Printed at 133% scale, it can hold calibration cubes

So basically:

1. Print carefully.

2. Do NOT stare at his eyes...