Extracted from http://www.shitokai.com/kata.php - a Good reading and Knowledge source
In this section, we are going to read about thirteen very fundamental points in kata that must be considered while practicing kata.
Yooi no kishin- Readiness, concentration, will, and determination against opponent before starting kata.
In'yo - Active and passive (i.e. knowing whether you are attacking or defending).
Chikara no kyojaku - Correct method in using power, the amount of power used for each kata movement and position.
Waza no kankyu - Speed used in each kata movement and position.
Tai no shinshoku - the amount of contraction and expansion for each movement.
Kokyu - Breathing, right exhalation and inhalation in each kata movement.
Chakugan - Look spot, considering the aim and destination of technique.
Kiai - Shout, in one or more certain points, shout shows the soul of fight of kata. Additionally, the whole conducted power is released.
Hyoshi - Rythm. Proper accentuation and flow of the movement of kata and each combination of kata.
Kime - Focal point or Focus refers to the concentration of all the energy of the body in the instant a particular technique( blocks, kicks, punches and...)makes contact with its target.
Antei - Balance. Stability, adjusting, figure and using the proper and correct stance in each movement.
Keitai no hoji - Using each technique in its proper place.
Zanshin - Being fully aware, being in guard position at the end of kata. Looking towards the side kata is finished.
Today we can see that many karatekas do not practice kata seriously and do not realize the usage of kata. In fact, it is true that kata will be useable only for those who have studied it deeply and have perfect recognition.
Rey (Bow)
At the beginning and at the end of the kata, one bows. This is part of the kata. When doing kata successively, bow at the every beginning and at the completion of the final kata.