Sand the nasty fairings. It's important to have an appropriate area for for beginners and colour to adhere to. Sanding the fairings will create this area for you. To do this, use 400-grit emery paper. Sand the entire area of the nasty fairings using round activities, while applying moderate pressure.
Prime the outer lining area of the fairings. Without for beginners, the colour will not stick properly to the fairings.