I need help to make mold

i want to make mold but i’m some struggle to make mold.
what is simple and efficient way to make mold with this model.
thanks so much!
Dazzling Waasa-Jaagub (2).stl (45.5 KB)


Just put the model in a box, then model a hole to pour in the filler. Then use a plane to slice the model in half into two halves. Then add some teeth to hold the sides in place. Here I made it into a mold for you.
Mold.skp (370.6 KB)

P.S. Whoops… I forgot the hole. Hopefully, you can figure out how to model that part.