How can I make a curved surface with the edges perpendicular to the surface face?

Hey everyone, I am trying to work on several chair designs but I am unsure on how to make a curved surface with perpendicular edges. Attatched are some photos of the chair I'm trying to model. The only way I know of doing it now is to draw the side curve face, extrude that then cut it from the top, but that leaves me with edges perpendicular to the solidworks work plane.

Thanks

SolidworksParts And Features