If you wish to be employable, I would try a different career. Teaching in the arts is extremely competitive because many artists use teaching to support their studio practice.
To teach at most colleges, you need a Masters degree in the area of specialization. Many community colleges and private art schools will waive the MFA requirement if you have significant experience (like you are already a super famous artists), or your specialization is in high demand (such as graphic design or web building).
If you plan to teach high school or elementary, I recommend specializing in a couple subjects. Then you have a competitive edge and can also sub for different subjects. I don't know much about the certification where you live, but in California you can look it up on the state website. I believe it requires both a 4-year degree and a period of internship where you get practice.
As far as being "effective," well that is a skill that will develop through practice (graduate school or other training), and continuing to learn from your mistakes. I recommend studying a broad range of complementary subjects to help you in your teaching career: psychology, ethics, speech, history, science, sociology, and on and on. Always have patience, always safe everything from all your classes, listen, have a sense of humor, etc.
Good luck, but honestly it is extremely hard to make it as a teacher. But, the reward a a job well done makes it worth while.