How to paint engine bay?

spay with good degreaser pressure wash then use wax &grease remover if it has been painted with rattle cans before strip with rilock disc sand,wash again with wax&grease remover prime,paint if it is orignal paint just sand the rust spots out & were you sanded thourgh &prime be sure &read the paint mfg recomomedations try to avoid rattle cans if possible cheap paint is not good good paint is not cheap &dont paint black unless the car is black