Gleaned from https://www.faa.gov/uas/registration/faqs/:
Here are the basics for hobby/recreational drone operators:
• Register your drone on FAA.gov before first flight outdoors.
• Put your FAA registration number on your drone(s) – anywhere that is accessible without using tools, and be prepared to provide your registration certificate upon request. If you have multiple drones, only a single registration is required. If you sell your drone, remove your registration number so you won’t be held responsible for future drone operators.
• Do not fly within 5 miles of an airport unless you first contact the airport manager or air traffic controllers. Contact numbers can be found here.
• Remain well clear of and do not interfere with manned aircraft operations, and you must see and avoid other aircraft and obstacles at all times.
• Do not fly near or over sensitive infrastructure or property such as power stations, water treatment facilities, correctional facilities, heavily traveled roadways, government facilities, etc.
• Do not fly over your neighbor’s property or anywhere else someone might have a “reasonable expectation of privacy.” This is one of the “community standards” the courts will rely on if you are sued for an invasion of privacy or trespassing.
• Do not fly over people’s heads at a sporting event, public gathering or park. Stay at least 25 feet away from persons or vulnerable property.
• Keep your drone within your line of sight and fly no higher than 400 feet.
• Do not operate your drone while under the influence of alcohol or drugs.
• Do not shoot down a drone, even if it’s flying over your property. This is the same as shooting at an aircraft. It is a crime and you will be arrested.
The current rules apply only to personal and hobby, not commercial use, which could put you into a category that requires getting a pilot’s license and specialized training.
Other useful resources: