6. When done, with the curve still selected, I then go to Edit, Duplicate another curve and translate it up to the position I want. (Figure 6)

(Figure 6)

7. Then I select both curve and perform loft to form a surface. When the surface formed, I select the vertical isoparm somewhere in the middle, then detach it. This is to split the surface into 2 so that I can create more organic look.
(Figure 7)

(Figure 7)

8. Don't forget to delete history after you have detached the surface. Go to Show, none to turn off every object, again go to Show, Curves to display only curves in the window. Then delete all curves. After all curve deleted, go to Show, All to turn on all object display. Or you can pick mask curves to pick curves and delete it. (Figure 8)

(Figure 8)

9. Then I will rebuild these surfaces. Select 1 surface, Ctrl-a to bring up Attribute Window. Note that Min Max Range of UV are not matching with Spans UV. By rebuilding surface we can make them matching each other. Go to Edit surface, Rebuild surface, tick CVs in Keep column, then click rebuild. (Figure 9)

(Figure 9)

10. Now, I start to pull the CVs of the surface into the shape I want. After I had done, I duplicate them and translate them inside. This will use to create thickness of the broken surfaces. (Figure 10)

(Figure 10)

11. I now select 2 isoparms edge from 2 surfaces and loft them. The result is shown as picture below. (Figure 11)

(Figure 11)