It is quite common to get dust, dirt and fingerprints on the glass element on the front end of you lens. Here are 3 tips to keep your lens clean!
Avoid touching the glass. It leaves smudges and fingerprints. So mind the fingers, especially when you try to clean your lens.
Use an air blower. A small blower works great for getting rid of dust and dirt from the front of your lens. These can be purchased easily online or from most camera stores.
Use a microfiber cloth for any smudges or fingerprints. Gently wiping your lens with a clean microfiber cloth until your lens is clean. Try to avoid using your clothes, paper tissues or other harsh or course materials as this might scratch the glass. Store any microfiber cloths in a place that is dust and dirt free. It’s important that the cloth stays clean too.