Never leave food, garbage, or other perfumed products inside your tent. Jays, squirrels, and squirrels can quickly snatch food in broad daylight, and other animals come looking for food at night. There is also the problem of chemicals in your toiletries that contaminate water sources. Always be sure to use biodegradable soap when camping.
Even biodegradable products have an environmental impact. Soapy water should never be thrown into streams, lakes, ponds, etc. It should be disposed of 200 feet from any body of water. Usually, you'll need to make sure you start a fire away from your tent, but sometimes the fireplace is already in place when you arrive.
When this is the case, be sure to place your tent at a safe distance from the flames; this will depend on the size of the fire and the direction of the wind (sparks that fly are the greatest danger), but as a general rule, try to keep a distance of 40 feet between the fire and the tent. Also, let the fire go out before retiring for the night. They're essential if you're camping in a country of bears, and you should use them to store not only uneaten toiletries and food, but also garbage. Some sites include bear-resistant lockers, but it's best to bring your own storage solution just in case (and in some places, the law requires it).
Bear bags are good, but cans are better. You can get them in a variety of sizes and should be kept at least 200 or 300 feet away from your campsite (and other campgrounds and trails as well). If you're using bear bags, make sure you hang them properly. Your personal safety and the safety of animals.
Usually, you don't store food in your tent because animals come looking for food. What brings you face to face with a wild animal. Using insect repellent, wearing long-sleeved blouses and long pants will help prevent bites. Be sure to keep tent mosquito nets closed whenever possible and don't leave containers of water and beverages open around the campsite, as they can attract thirsty insects.