Not for carnival only
Normally I would have some photos, but we made the project in the education center together with our students ... but hopefully the explanations gonna be useful for you.
When you start you first put lots of clay on the plastic bowl. In this way you are forming the base form for your future mask. When you are done with nose, eyes ... everything you need to put plastic wrap on the finished base form.
In this way the clay will not dry and also the paper will not be sticked together with the clay.