In order to avoid cross contamination you should do the following:
Safe and seperate: Keep raw fish, poultry and other raw foods away from cooked foods and ready to eat foods.
Use different dishes: Use different equipment for handling raw and cooked foods. use seperate chopping boards for raw and cooked foods. If using a single chopping board, wash it well between uses.
Dont hand germs on: Keep germs away from your food. Cover all cuts,burns and sores with waterproof dressings and change these regularly.
In order to maintain cleanliness do the following:
Wash hands well: Wash hands before and after handling food. Between handling raw foods and touching any other food or kitchen utensils.
Wash and wipe: Wash utensils and kitchen surfaces after preparing foods. Wipe down sinks,taps,fridges and cooker door handles.
Put a lid on it: Cover all waste and rubbish bins. Clean bins out with hot waterand disinfectant at regular intervals.
Germ warfare: Use the right materials for cleaning. Use tea towels and dry them thoroughly. Have different cloths or sponges for separate tasks.
Keep your food chilled:
Fridge foods, these foods belong in the fridge: Raw meat, fish, poultry, dairt products and eggs. Foods with a 'use buy' date or label that says keep refrigerated.
Fridge temperture: Keep the coldest part of the fridge at no more than 5'C and the freezer at -18'C. Check this regularly.
Chill out time: Do not put hot foods in the fridge.
Meat needs heat: Know which meats must be cooked right through. Always cook sausages, burgers, pork and poulry right through. Dont let raw meat touch or drip onto foods that are already cooked.
Stir and stand: When using a microwave, stir foods and drinks and let them stand for a couple of minutes.
Heat then eat: Cook all foods until they are piping hot. Dont cook foods too far in advance. Keep cooked foods covered and hot above 63'C until it's time to eat them or cool and store them in a fridge.