you won't see much happening. the solution is saturated, so the salt will fall to the bottom of the container and sit there. it will not dissolve.
however, at the atomic level, na⁺ and cl⁻ ions are being pulled from the surface of the crystals and going into solution as hydrated ions. at other places, na⁺ and cl⁻ ions are returning to the surface of the crystals.
the process is
nacl(s) ⇌ na⁺(aq) + cl⁻(aq)
the rates of the forward and reverse processes are equal, so you see no net change.
examples of reversible changes. melting: melting is when solid converts into a liquid after heating. example of melting is turning of ice into water. example of boiling is turning water into water vapour.