5 basic rules of firearm safety
1. Treat every firearm as if it is loaded.
It is important to create a mindset of this while dealing with firearms. Even though a firearm has been checked, even if someone claims to know the status of the firearm; the utmost safest idea is to handle a firearm is if it is loaded.
2. ALWAYS keep the muzzle of the firearm pointed in a safe direction.
This is also a constant state of thinking which is important when handling a firearm. Be conscious of where the firearm is pointing and always remind inexperienced shooters of this important rule.
3. Always keep the manual safety (when available) on until ready to shoot.
A manual safety provides a back up to your primary safety, which is stated in rule four.
4. Always keep your finger off the finger until ready to shoot.
Your finger is your number one safety. You should always have control over the firearm and it should never have control over you. Do not rely on manual safeties. Doing so is a bad habit, especially if you come across a firearm with no manual safety. (Many firearms do not). Keep your trigger finger off the trigger itself, and outside of the trigger guard. The best way to achieve this is by practicing playing your trigger finger along the side of the firearm, not in the trigger guard directly.
5. Always been aware of your target and what is beyond it.
Bullets and projectiles travel at hundreds of feet per second and carry with them tremendous destructive power. It is not enough to think only of your target. Make sure there is a clear backstop behind your target when shooting in a controlled environment. If you are engaging a hostile target, be aware of any bystanders beyond the target zone.
In addition to these rules, remember that it is always recommended to wear ear and eye protection when using a firearm or being around someone who is.