I was asked how to make the my Ducati seat cowl in Catia. Unfortunately, I haven't worked in Catia for years, the model was made in Solidworks. Having worked in ProE, CATIA and Solidworks - though menu pics and verbiage may be different, they and other systems, are all capable of creating the same features with similar steps. I created a simplified PDF that shows the basic - steps taken to create this seat. These steps can be used as a frame work to design a wide variety of parts and on several CAD platforms. There are a lot of ways to do things, hopefully you find some of this useful.
The model can be downloaded from GrabCAD. It is named: Ducati 996 / 998 Cafe Race Seat.