Everyone knows that elite athletes use mental imagery and relaxation techniques to enhance performance. The same applies to pianists. (And they don’t have to be entering the Tchaikovsky Piano Competition to practice refining staccato at varying intensity.)
I favor sports metaphors in the lesson environment.
Simply bounce a basketball using forearm impetus to produce a big, robust effect, and then substitute a ping pong ball to garner the lighter, but still lively rebound motion.
Regardless of dynamic level (loud or soft) the player must funnel energy through relaxed arms and supple wrists to PROJECT his staccato and make it worth the effort.
(A low impact bounce is always preferable to a clunk!)
The following Skype lesson-in-progress (Berkeley CA to Greece) demonstrates: