Some dust is little pieces of cloth. Other dust is little pieces of rock. I have seen many a camera lens with tiny circular scratches from people rubbing the rocks into their lens coating. Gently get all the dust off. Then go after any oil or fingerprints with lens cleaner and lens tissues. The cheap Costco lens cleaner used for eyeglasses is fine. Lens tissue is cheap, and well worth it to avoid accidentally cleaning your lens with a soft cloth that has picked up a hard piece of grit.
There was a time that I had to clean laser mirrors that were subject to a large amount of energy. Those have to be immaculate or they self-destruct. It sort of changed the way I treat lenses.
