How do you make the noncount noun sawdust more than one?

You can't make "sawdust" plural because it's a noncount noun.

Noncount nouns represent things that can't be counted individually, like liquids, substances, or concepts.

Here's how to express more than one "sawdust":

* Use a quantifier: "a lot of sawdust", "piles of sawdust", "bags of sawdust", "some sawdust"

* Use a measurement: "two cubic yards of sawdust", "a bucketful of sawdust"

For example, instead of saying "sawdusts", you would say: "There were piles of sawdust on the floor."