In other to stop bacteria from escalating.
Firstly, get your hands washed before cooking or touching any food, hands are ignorably form of transmitting Bacteria...
Do not allow raw foods such as meat, fish and vegetable to touch other foods (cooked foods), unless still on cooking process.
Don't use any material used on raw food such as knife, chopping board on already made food, unless they are rigorously washed.
Do not wash raw food (e.g: meat, fish) with out cooking, added with little salt, they must be partly cooked (parboiled) before washing...