Select materialType as 2D, blendFunc to Blend, tile to NO TILE, link to the image.
Build the material.
Copy raw/images/linked_image to mods/yourMod/images/
Go to your scripts folder create a new function or use it in an existing one (one that you created).
First precache the shader by using the function PrecacheShader("shader");[/u].
Function should include hud_spawn = create_simple_hud(self); //self represents the entity the function was called from so you better have called it like this: self thread newHUDElem or whatever entity self is BUT MAKE SURE IT'S A PLAYER.
mod.csv should include the material by doing: material,material_name