How to remove stains, scratches or birds' droppings?
Firstly wash with water.
If remains, use "Cleaner".
Usage of "Metal remove clay" is also effective.

How to remove water spots?
Water spots may happen when drops of water dry on a water-repellent surface.
In most cases just wiping with a bit wet AQuly cloth can remove them.
If remain, use "Cleaner".

How to prevent water spots?
In case of dark color cars, keep shorter interval of washing in summer. 
Try to find in earliest timing. If any, wash it as soon as possible.
Dry car body 
well by wiping with a dry AQuly cloth after each washing.
AQuly cloth can be used several times, just regularly wash in a washing machine.