First thing you should do is to get a moist cloth or sponge and wipe the paint before it gets dry.
If it gets dry then identify the paint mark and if it is a water mark place a wet cloth or towel over the paint spots. This process will soften the Paint mark without any damage and you will easily remove it from the car body with a dry towel.
If the paint mark is not wiped off then pore some more water on towel and keep it for few more minutes on the paint mark and then try again with the dry towel.
For the enamel paint marks you will need a paint thinner or mineral spirits. Take soft towel and soak it with paint thinner or mineral spirits and gently rub it over the paint mark working your way to the center.
Once the paint starts coming off wipe away any excess paint or drips with a clean dry cloth.