General Precautions:
Wipe up spills right away. Citric acid, acetic, tannic acid can etch your stone and dull the polish finish.
Cleaning:
Use New Kitchens, Inc. proprietary cleaning solutions mentioned above.
Cutting, Scratching Natural Stone:
Granite is very hard and is in the range of 6-7 on the scale of hardness. Knives are made of stainless steel which is an alloy of Iron-Carbon Chromium and Nickel and is in the range of 4-5 on the scale of hardness. Therefore it is likely knives will become dull rather than harming granite surfaces. However, you can chip granite if you hit it with something hard... like a hammer.