I highly reccomending reading about PBR workflow in UE4, it’ll help you understand how to create really nice materials and what all the inputs do! But to make your material less plastic-like, plug in a constant value of something like 0.7 or higher into the Roughness input. If you’re using 4.11, try out the new Cloth shader. It’ll produce a nice fuzzy Fresnel effect that soft fabrics tend to have.
Sorry but that’s incorrect, I think you might be thinking of another engine? In UE4 Roughness value of 0 makes it reflective like chrome, a value of 1 makes it like chalk. If nothing is plugged in it’ll default to 0.5.