Hello!
While I love teaching adults!, I don ´t think I can ´t give you a quick crash course in teaching adults but some tips that work for me :)
Unlike most teenagers, adults are eager to learn. I use about the same oral and written activities I do with teenagers but sometimes I make some changes. We work the speaking part quite a lot with pictures, flashcards, role play, because most grown ups are studying English for their current job or a future one, so expressing themselves in English, communicating with their classmates or with their teacher in English is very motivating for them. Even with beginners, on the first class, I usually give them a worksheet with useful phrases in English for them to use in class as much as they can and they do!
And last but not least, even though they are adults, they love games! We ´ve played tic tac toe, double or quit, snap, etc and songs! always related to what they are studying. Last year I had a group of adults that if a week went by without a song...they would go ...teacher... and the song???? They loved it!
Another suggestion would be to place yourself as a student, sometimes I think ok... if I were learning a language, what type of class, what topics, what type of exercises I would like? Since we are also adults, what works for us, it would often work for them too :)
Have fun
Regards :)
Jorgelina