If you have just opened a fresh package of polymer clay, and the clay feels too soft, sticky and almost runny, it is absolutely normal.
When the clay is fresh from the factory, it is quite wet. It is done so that the clay can be stored for a long time without losing its softness. If your clay is very soft now, it will become harder with time.
There are ways to make clay stiffer faster.
1. Mix very soft polymer clay with older polymer clay.
2. Take your polymer clay out of the package and leave it in the open air for a day (or longer, if required). Protect the clay from dust with a sheet of paper.
3. Leach out polymer clay by using printing paper.
- Place a thin layer of clay between two pieces of plain printing paper
- Roll this sandwich in a pasta machine or with a simple roller.
- Mix the clay.
- Repeat if necessary.
4. Leach out polymer clay by using cornstarch instead of paper. Place your clay in a bowl of cornstarch and cover with more cornstarch.
The printing paper or cornstarch will leach out some oils and plasticizer, making your polymer clay more user-friendly.
Make sure to check often, some brands will leach within 3 minutes, others will require hours.