Q&A for How to Sculpt Using Polymer Clay

You do not need a slip. You simply take the clay out of the package, condition it in your hands, and sculpt.

The clay should re-bake perfectly fine if you bake at a slightly cooler temperature (say, maybe 260 if the recommended is 275, as it is for most polymer clay).

The liquid is likely isopropyl alcohol (also known as rubbing alcohol). This partially melts the clay and aids with smoothing its surface. It evaporates quickly and the clay will then return to its original consistency.

Polymer clay would likely be too expensive for a solid sculpture that large (also, the baking time would be very long and likely cause cracks on the outside), but it would be suitable for the outer layer (4 to 10 mm thick, depending on the intricacy of and accuracy of your inner layer). Bear in mind that you will need to bake the sculpture in an oven, so you may prefer to make it from smaller sections and bake them separately.

You will most likely need clay tools to help create details on your project, but that's all.

You can put multiple plates in the oven and as the smaller parts gets finished, you can take their plates out of the oven, close it again and wait for the rest to finish.

You could knead or warm the clay to soften it, or just mix it with newer clay.

Since the ceramic pot is already fired, the oven should be fine. Polymer clay baking temperatures are normally around 275ºF (check the instructions for your particular brand), which most ovens can meet. What I would worry about in this case though, is the fact that the polymer (after baking) might not stick to the ceramic. A solution might be to bring some rough sandpaper to your pot.