Food Safety 101
What is "cross contamination" and how do I avoid it?
Uncooked meats and eggs are easily and often contaminated with pathogens such as salmonella and E. coli. Cooking these foods past USDA recommended temperatures is usually enough to kill any potential food hazard when eating, but when handling raw animal products before they are cooked, pathogens can remain on cutting boards, knives, and other utensils, and they can make their way onto foods that we will eat raw. For example, if you cut raw chicken on a cutting board, you can't start chopping salad greens on the same cutting board right after. It's extremely important to wash all materials that touched raw animals products with hot water and dish soap, as well as your hands.
I made too much food! How do I save it for later?
Store foods in the refrigerator and freezer in airtight containers. Always let food cool down (but not more than an hour) before storing -- warm food can raise the temperature of the refrigerator/freezer and spoil the rest. When reheating food, always reheat it to a high temperature (bacteria love lukewarm) and never put reheated food back in the refrigerator or freezer.
How long can I keep food?
Don't keep leftovers in the fridge much longer than 2-3 days. Raw meats shouldn't stay in the fridge longer than 1-2 days. If you buy too much meat or are planning to cook it later, freeze it right away, and thaw overnight in the fridge when you want to use it. For veggies, storage time and place varies. See this chart from UnlockFood for guidance.
Practice "First In, First Out"
I learned this phrase working at a local bakery, and even though I did it at home subconsciously and it's common sense, I find it helpful to keep the phrase in mind when I'm cooking. All it means is that you should eat the oldest things first before eating newer stuff. You don't open a new carton of milk before finishing the first. This just ensures that you have less waste and spoilage. If you want to get even more organized, keep a roll of masking tape and a sharpie by the fridge/freezer and label everything with the date before storage. In addition, if you're stocking up on things you already have (ex. buying a new carton of milk before finishing the first), put the new item behind the older item to ensure you reach for the old one first.
Wash the Outside of the Fruit and Vegetables...Even if You Don't Eat it
Avocados, lemons, pineapple, melon: it is advisable to wash the outside of these fruits because cutting the knife through can bring with it whatever dirt/pesticides/fecal material on it from the outside.