Because there are variables beyond my control (clays, papers, water, mixing errors and etc) always pre test fire what you have before a big project. No guarantee can be offered that 'alternative" commercial paperclays now on the market will meet the all the performance advantages of my high performance trademark P'Clay® brand only available from licensed manufacturers/distributors.
To get instant hollow shapes, fold cutouts.
1.use a stick, pencil or needle tool to scribe the pattern like you do in sewing projects.
2. Let your cutouts out in the air to stiffen slightly- maybe a half hour, and you can fold them and roll them into shapes like below.
folding cutout shapes
Cutout soft slabs--rolled out on a soft surface like pastry dough with a rolling pin. Remember to lift turn the slab over in between each "roll over" with the pin to keep p'clay from sticking to the table. Roll the pin with light-medium pressure multiple times to flatten the lump gradually rather than try to compress it all the first go. It may be easier to slice off a thick bread slice from your chunk of soft clay with a wire tool to start. If you want texture try stamps like with traditional clay.
Soft P'Clay sheets can be draped, curlled, rolled like fabric, cut into ribbons, woven, scored, and more. Tiles can be made also.
Let these stiffen to bone dry and they are tough to serve as an armature to support successive layers of wet soft p'clay.
Twist a ribbon of soft p'clay, arrange it as you like, then let it harden to bone dry. Assemble the bone dried riboons and twists when they are easy to hold and strong.