The problem isn't guns, the problem is criminals, the mentally ill, etc getting their hands on them (and other reasons not related to guns). This occurs through (currently legal) purchases at gun shows, and theft.
This can be accomplished by:
1) Closing the "gun show loophole" and require background checks on anyone purchasing a firearm from any other person/entity
and,
2) Requiring ALL gun owners to own a gun safe that cannot be easily carted off and requiring those gun owners to keep any and all guns that are not currently being used or are not on their person
and,
(b) any and all guns that are in their residence, vehicle, etc while they aren't present
to be locked and secured in the gun safe.