Here's what you need to do to become a Medicine Cat:
1) Have had been given herb training by their mentor.
2) Have practiced the healing system and know how to use it.
3) Have been given battle practice and know how to use the battle system.
4) Have been to at least one Gathering.
5) Have been to at least one Medicine Cat Meeting.
When you have met all of these requirements, please pm your mentor and tell him/her that you have. They will hold your ceremony when they are ready. Also let them know what you would like your medicine cat name to be.
But, not only do you need to have met the requirements to receive your medicine cat name, but you need to be seen fit in the eyes of the other medicine cats that you deserve to be one.
P.S. At the moment, I have taken over all leader and some apprentice training duties. So please pm me if you have met the requirements. Read this for more information.