A little dust on the lens won’t affect the image, so don’t be compulsive. Keep the lens covered when not in use to reduce the amount of cleaning required.
When necessary, use a soft brush, such as a sable artist’s brush, and a blower (an ear syringe makes a good one) to remove dust.
Fingerprints can be very harmful to the lens coating and should be removed as soon as possible.
Use a lens cleaning cloth (or roll up a piece of photographic lens cleaning tissue and tear the end off to leave a brush like surface). Put a small drop of lens cleaning fluid on the end of the tissue. Never put cleaning fluid directly on the lens; it might run between the lens elements.
Using a circular motion, clean the lens surface with the cloth or tissue, then use the cloth or a tissue rolled and torn the same way to dry. Never reuse tissues and don’t press hard when cleaning because the front element of the lens is covered with a relatively delicate lens coating.