Camera Lens Cleaning Kit

First things first. Do not clean your camera lenses if they don’t need it. Your camera gear has special coatings and chemicals used in the production and maintenance of said piece. Lenses and sensors are at the top of the list.
You can wear these away with excessive cleaning. You also allow for further problems, such as scratches, as your lens is open to the elements again. Store it in a camera bag with the lens cap on to minimize the problems.
Stay away from acetone. This is a great cleaning fluid, but when used on cameras, it has adverse effects on the plastic and painted elements. Just don’t use it. The same goes for household glass or window cleaning liquid. It isn’t worth saving money, to then spend it on a new lens.

Also, if you introduced your lens to sand (accidentally dropped) then in no way, shape or form should you wipe a cloth over it. This will cause permanent damage. Start with a blower, for example, or pass it on to a professional. There is only so much you can do.
It is also worth noting that different lenses mean different chemicals. Some of the chemicals mentioned in the cleaning kits may not be suitable for your lens or equipment. Check with your brand or representative first.
Keep your microfibre cloths in an airtight and clean container. Check them first for any dirt or dust you may be placed back on your lens. Shake them first, and work with small amounts of pressure, building up if needed.