I'm still making resin castings as 500 ml of resin is a lot for casting such small pieces. Finding out that latex moulds can be used with resin was really great, because I can make moulds for casting just one pair. You can't really use a special design, like the one for Monster High Nefera in the picture below, for a lot of shoes.
As you can see, the parts used for the master are really simple, just wooden and plastic beads, a round wooden stick (for keeping the heel parts together) and card stock. The main things are that the master lasts long enough to make the mould and that there are no openings between the parts for latex to get into (two coats of sealer will take care of that).
In the next picture, the master is attached to a base with clear mounting tape and two coats of sealer have been applied. This is for making the latex mould, which has been described in previous posts.
Here you can see the finished mould and the pair of castings. The part of the mould between the heel and sole needed to be cut a bit to remove the castings and turn the mould. Those parts of the sole were so close to each other that too much latex collected there when making the mould.
I also made a couple of pairs of soles for Miss Piggy. The masters for both designs were made of card stock (sole) and wood (heel). The Barbie wedge sole is included to show the scale.
With such a long and thin sole, it was necessary to have some extra support during the casting process. I removed the heel from the master and used the curved sole under the latex mould to ensure that the mould would keep the correct shape.