1. Sketch two shapes. One will be the Extruded shape and the other will be the path.
  2. In this example: the circle is the extruded shape (make sure it's positioned in the right direction) and the complex line is the path.
  3. Double tap on both the shapes.
  4. Select 'Extude' from the contextual menu
  5. Then select 'Along Path' from the contextual menu
  6. Drag the extrusion knob (the orange knob) along the path
  7. You can also switch between between the shapes if you feel adventurous :)