Because your camping trip is a brief one, do not pack a lot of clothing. You do need to understand the weather of the Sierras during summer, and pack wisely. This mountain range usually has late afternoon thunderstorms, so pack a raincoat or poncho. Take a jacket to wear during evening when temperatures begin dropping. Also pack a short-sleeve and a long-sleeve shirt. For hiking, wear long pants and hiking boots to avoid cuts and scrapes from bushes. If you plan to swim in Lake Tahoe, pack swimming gear.
Pack your own cooking utensils such as pots, pans and a lighter. The Sierra Nevadas have many lakes and streams with plentiful fishing. Obtain a fishing license when arriving, to avoid paying expensive fines. Make sure you have a fishing rod and bait. Catch enough fish for all members of the camping trip to dine on for dinner, and for breakfast, if you choose. After cooking the fish on the campfire, extinguish the flames by spreading sand over the fire's embers.
The Sierras feature Mount Whitney, the highest peak in the contiguous United States. The farther up the mountain you travel, the less contact you will have with others. Always travel with your cell phone, but remember it may not receive a signal at higher altitudes. Include flares and light sticks to use as communication signals if you have trouble or face danger. Wear a waterproof whistle around your neck if you need to make noise to signal attention.
Pack a first aid kit to treat any minor emergencies. Include bandages, antibiotic cream, tweezers, alcohol and a knife in the kit. Even when you take preventive measures, accidents -- such as falls or cuts -- can happen in the wilderness. The Lake Tahoe area has over 300 days of sunshine per year, so it is important to put sunscreen on exposed skin to avoid burning.