How do I clean the objective lens?

How do I clean the objective lens?

Blow dust off of the lens with blower. When the lens is stained by fingerprints or grease, blow off the dust or dirt on the lens surface, and wipe the surface lightly with clean gauze or lens cleaning paper soaked in a mixed solution of 2 parts absolute alcohol to 8 parts of ether.

Notes:

1. If the lens surface is rubbed too strongly, or when dust or dirt still remains, it will be scratched. Also, if the lens is soaked excessively with cleaning solution, the surface will be stained.
2. Do not wipe the lens with disinfecting alcohol, since it contains a high proportion of water and will image the surface.
3. Do not use silicone cleaning paper.