Much like many of you out there I wish I had more of one specific bit or piece to use on my minis.  Be it a Terminator head or shoulder pad icon or weapon.  GW likes to build its kits in ways that require us to buy multiple ones, examples are blasters in dark Eldar, Missile launchers in Space wolves, and combi weapons.  So I decided to experiment with replication of bits I plan to use for my dragon warriors.

Here is the result of my first two part Mold, The terminator helm is 100% Greenstuff and for my own use only.  On a side note, I would appreciate any tips on making Green stuff stronger.
Edits from Comments.
I used a two part mold made from insta mold. I had to make the bottom mold first then do the top. I also designed my mold halves to fit in a pair of 25mm bases. Doing that let me press the two halves in a vice to press out extra green stuff and allow it to cure. This leaves some hellish flash but that was easily cut away with a knife and steady hand.

And WarFog was kind enough to post his guide on casting with Procreate which can be found Here @ Warfog's Blog.