Teaching isn't the easiest of things and it takes time to acquire sound skill and knowledge. However, you can speed up that process and I find the Oxford series of handbooks invaluable at providing teachers with easy, basic and communicative lesson "cores" or ideas upon which they can build their skill.
They give you what the textbooks don't! How to teach simply described through 30 basic lessons in each book. Low tech, and all are very communicative. There are handbooks on the 4 skills (Speaking / Listening / Reading / Writing), also grammar, culture, classroom language and more.
to preview all these handbooks and then buy the ones you like. They are cheap! Invaluable and the perfect books to help you become a very skillful teacher. Thank you Jill Hadfield!