I sketch an equilateral triangle along the outside surface of the bolt or rod where the threads need to be with the base along the surface and the other 2 sides pointing toward the center. Repeat the pattern as many times as needed, then do a revolve cut with the axis of rotation being the axis of the bolt or rod. The dimensions you use need to be chosen to approximate the pitch of the threads you're trying to emulate.
I only use the view for reference, usually in an isometric. As you say, its for cosmetic purposes
HTH