Many people ask when they can become a Reiki Master. My thoughts on this subject are a bit different from the majority of instructors in the U.S.
As a Reiki Instructor, I encourage my students to practice, practice, practice. Practicing and understanding energy is so much more important than taking a class and receiving a certificate for the next level.
In the U.S., many if not most instructors teach Reiki I and then Reiki II 21 days later and the Master level 21 days after that. In my mind, to be a Reiki Master, the student should be an expert and ready to teach. I don't know about you, but I have never "mastered" anything in 42 days; therefore, I will not teach the master/instructor level unless the student has an excellent understanding of energy and how to use it.
The fundamentals of Reiki are being able to scan a person's energy and understand which areas feel different and how they feel different and being able to send and move energy to help the person move toxins that are "stuck" in the body in order to feel better.
In addition to understanding energy, I would expect that a person interested in becoming a "master" have performed at least a hundred sessions, attended and assisted in level I and II several times (and possibly with several instructors) and gone to as many Reiki shares as possible. Reiki shares are really the key to understanding Reiki and improving your skills. You gain so much knowledge and confidence from practicing with others who learned from different instructors and have different ways of performing Reiki.
It is also important to read as much as possible about Reiki and to be familiar with the teaching and opinions of the leaders in the field. Frank Arjava Petter, William Rand and Tadao Yamaguchi have all written wonderful books. From what I understand, Reiki in Japan was taught in 6 levels when Mr. Yamaguchi's mother studied with Dr. Hayashi. She took the final 2 levels which allowed her to teach more than 4 years after she began her Reiki studies. Even Mrs. Takata (the woman who brought Reiki to the U.S.) waited quite a while before becoming and instructor. Other time frames I have seen for people following the traditional Reiki path have been as long as 7 years.
When Westerners first contacted Mr. Yamaguchi's mother to learn about the Japanese Reiki tradition in Japan (from Light on the Origins of Reiki), she asked the Westerners what diseases they had cured as Reiki Instructors and was surprised to learn that they hadn't cured any. This is largely because we avoid treating medical conditions in the U.S. and we never try to cure any illness but say that Reiki is self-intelligent and will travel where it feels it is most needed. That being said, every experienced Reiki Instructor has received feedback from clients who had medical tests before Reiki and after Reiki and have had documented improvements even though the only intention of the session is to relax and enjoy. Receiving this feedback is one of the indications that you may be ready to become a Reiki Master.
When you take a Reiki class, the first class may seem foreign to you, but when you repeat level I several times, you gain new understanding each time and the strength of your energy increases with the attunements you receive in each class. Repeating level I and II is free of charge when you study with me and attending Reiki shares is MUCH more important than advancing to level II before you are ready.