Here is a breakdown of my process for setting up my molds. I believe that everyone should learn from everybody and adapt it into your own way of doing things. For molding i have learned from mark alfreys videos, jordu schells video, and john browns video. I have taken what works for me from each one and here is how i do it.
First i use foamcore to make a wall close to the sculpture. With laying it on its back i dont make as much of a mess and i dont waste plaster. Just making a mold wall and doing the back half first the plaster drips a lot and doesn't pile up as much on the sculpture. By doing it this way the plaster that drips off drips into the mold wall which i have pictured later. For the back of the head i lay it on some clay wrapped in plastic wrap so the back of the sculpture does not get damaged. I have foamcore strips standing up for support and planks across to hold the clay wall. Everything is put together with hot glue.
This picture shows how if i need extra support in a area how i use small triangles to strenghen the wall.
Here i have made the clay wall on top of the foam and around the outside where i want the wall to stop i have made a clay wall. Here you can see how when the plaster drips off the face it will not be wasted and the wall of the mold can be made thicker much easier.
The next steps i did not get to take a picture of, but what i do is i mix up the plaster and do two coats. One detail coat and one with burlap for strength. Then turning the mold over i put vaseling on the plaster wall to make sure the mold comes apart and do the same to the other side.