Do not clean lens often, only as needed, small dusts will not affect picture quality

need - lens blower which blows clean air without dirt, at least two sheets of lens tissue, lens cleaner liquid

1. carefully blow away dusts on lens
2. one or two drops of lens cleaner to *moisture* one sheet of tissue (folded to fit), not too wet, keep the other one dry
3. lightly wipe on the lens in outward circular motion in one pass, note if you let it dry from here, you will see cleaner marks and traces,
4. change to the dry tissue (new and clean), wipe on the lens in outward circular motion, this removes the cleaner marks and traces
5. blow away leftover tissue fibers