First I built a cardboard template to get a sense of the size I wanted. I've always liked the extended fender flare look of the Abarth cars but I didn't want to go so extreme with mine. The real purpose of my flares is literally to keep the mud off my rockers, so I don't need exaggerated flares.
Once I had the cardboard template looking "good" I fiberglassed over that to create the basic shape and something to hold the shape/structure. Then using two part mix and pour polyurethane foam I built up the flares/flaps to fill in the shape.
Once I'm happy with the shape I'll glass over the foam and finish them off. So far I'm really happy with how they are turning out. The foam couldn't be any easier to work with. Once cured it is very firm but sands away easily allowing for easy changes and unlimited design options.
![Image](https://i.imgur.com/8TgBAb8.jpg)