As for higher level students I don't normally teach vocabulary as a planned lesson. However, it does come up all the time when we are reading. It goes like this:
1. They see the new word
2. I explain the new word
3. I write the new word on the board (they see it again)
4. I write some synonyms, explanations, examples, etc.
5. We look back at the reading to see how it is used
Ideally, the students would follow up by:
- writing the word in their vocabulary notes
- writing an example
- using the word in a sentence when they get a chance
- seeing the word again and recognizing the meaning easily