In addition to wearing your usual attire, you may want to consider adding a midlayer. A thick wool sweater can be really cozy or even a lightweight insulated jacket. That said, certain parkas come equipped with a removable lining. If that’s the case, the lining can double as a midlayer and you won’t need any additional garments. Unless you happen to be in the midst of a polar vortex, of course.
For additional warmth around your neck and core, pair the jacket with a scarf.