|There are 3 variables for storing a gun
Quick to Use
In self-defense situations, it seems best to store your gun on your person, in a holster with a round chambered unconcealed.
This will give you the quickest access to your firearm if you need it.
Safe from Others and Accidents
If you don't want others, criminals, children, and others, store it in the best, strongest hidden safe you can find. Also, unloaded as you can accidentally pull the trigger, or in some cases, the gun can go off if dropped.
Within the safe, the gun itself could be locked or disassembled to make it harder to use. Ammo could also be stored in a locked and separate location.
These are the two extremes.
Just because your items are locked up, doesn't mean someone can't get access to them. There are many videos on the internet on how to pick or break open locks.
I'd show kids safe firearm handling with a toy gun. You could even run tests on leaving a gun around with snap caps to see how they handle it.
Mentally ill, suicidal people or children in the home should change how you store your gun. Also some states have strict laws on how you store your guns.