The last tip seems the most obvious, but it cannot be overstated: Follow gun safety practices. Treat every gun as if it were loaded at all times, even if you are absolutely certain it's unloaded. You should keep the gun's action open and only load the gun when you're ready to use it. Never point a gun at yourself or another person. Practice muzzle control -- keep the gun's muzzle pointed in a safe direction. The safest direction is usually toward the ground.
Also, keep your finger off the trigger until you are ready to take a shot. While guns are designed so that your finger fits over the trigger in a natural way, avoid carrying a gun this way. Always keep your finger outside the trigger guard until you're prepared to actually shoot. You should also keep your gun's safety on until you are ready to fire.
If you plan to use a tree stand, you should tie a strong rope or cord to your unloaded rifle. Wait until you are on the stand and secure before pulling your rifle up after you. When you're ready to come down, lower your unloaded rifle to the ground first. Never try to climb up to or down from a tree stand with a loaded weapon.
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