The best tool is an ultrasonic cleaner. Distilled water, a few drops of an anti-biologicals detergent like Tween or Triton-X, a few drops of isopropanol, and 10 minutes in the US. No heat, corrosion, or other issues. Just removes hand oils, skin debris, fast food residue, etc.
Now I just have to go get me one of those. Home Depot??