When designing a resin toy you have to be aware that you have to work with gravity. The liquid resin can only flow where gravity can take it. Let’s say you designed a character. If his arms are up they will cast easily, but if the arms are down at your character’s side you will have to create a vent for air and resin to flow to that part of the mold. Glove molds are not easy to vent, so complex shapes may have to be cast in a two part block mold. The type of mold you create depends on the shape of the object you wish to make multiples of. I think it’s best to start out with a simple “lump” shape and a glove mold, and move on as you gain experience. All this information is illustrated and explained in detail in my book, How To Make Resin Toys by J.E.Moores.