Take the cloth that comes with your glasses or binoculars or rifle scope and dampen it slighty. As was mentioned before, paper products can scratch the finish on your LCD/LED monitor.

Use only water to dampen the cloth. It should take off anything you managed to get on your monitor. (soda, boogers, cheeto dust, "protien stains" etc.)

Don't dampen the cloth too much, a drop of water running down your screen might leak into the internals and short something.

Small circular patterns work best, rub lightly until the stains disappear. Re-dampen if it starts to get dry.

If any dust remains on the screen left over from the cloth, brush it away with a makeup brush. They have soft bristles that won't scratch, and will remove the dust without leaving any behind.

Most cleaning products will either leave a residue or use an agent that might corrode the surface of your monitor.