許多字的意義和用法應是有過各種遷移、融合、混合、回顧，等等。按我現在對此二字的感受，說得稍絕對些：

作 is closer to create, or to invent, which is an action driven by an original will or inspiration.

做 is more like to manipulate or to manipulate with. It is more a result of desire or planning.

Great artists or scientists 作

Most of the rest 做

Van Gogh 作

Gauguin 做

I never like Gauguin...