“How do I clean my camcorder lens?”
Clean your digital video camera lens very carefully. 
More seriously, you want a lens cleaning kit, including an air blower, lens brush, and if necessary a microfiber cloth and lens cleaning solution. My personal preference for the lens brush portion of a cleaning kit a LensPen, which avoids the need for a separate lens brush and microfiber cloth.
To clean your lens, be sure to use the air blower first to clean particles off the lens that would potentially scratch the lens. Next use the brush to remove any remaining particles. If you have fingerprints or other oily residue on the lens, either a LensPen or microfiber cloth and lens cleaning solution will remove remaining stains.
Almost any camera store should have the supplies mentioned above or you can find them online at Amazon or your favorite online retailer.
