How do we become a voice acter?

A voice actor is a very attractive job.A voice actor's work is various.And in Japan, many people want to become a voice actor.I think that it is related to nerd culture.

So, how do we become a voice actor?
There are some methods of becoming a voice actor.
1. Entering a voice actor training school
2. belonging to theatrical company
3. From child actor

The most common is that 1.Entering a voice actor training school.There is the following as a famous voice actor training school.
"Tokyo announcement academy"
Otani Ikue who is the voice of Pikachu(Pokémon) and Tony Tony Chopper(One piece) is graduated.
"Japan Institute of narration acting"
Hayashibara Megumi who is best known for her roles in Ranma ½, Neon Genesis Evangelion, Detective Conan, Pokémon and  Mitsuishi Kotono who is the voice of Usagi Tsukino(Sailor Moon) is graduated.
This is probably the easiest path at its beginning, but breakthrough chances are very slim.

Sometimes theatre actors are scouted by people in the anime industry to become voice actors.
Paku Romi who is voice of Edward Elric(Fullmetal Alchemist) is this type.

3 is a case which belongs to a play-for-children team from elementary and junior high school students' time, supports theatrical skills, and become a voice actor.
Furuya Toru who is voice of Amuro Ray(Mobile Suit Gundam), Hyuma Hoshi (Kyojin no Hoshi) is this type.

And in others, the person who became a voice actor from the idol or the entertainer is also. But to become a voice actor is the strait gate.