Detached Hammer?? what do i do?

Hey guys, so my friend had a salinity spike and his green hammer detached itself from its skeleton?? didnt even know they could do that but he took it out gave it to me its chillin on the sand in my fuge and looks alive and well but what do I do now?? attach it like i would a frag? glue or tie to a plug? or do I just let it chill in the sand until it grows a skeleton again? i feel like that would take forever. thanks for the help