For nouns and verbs, I generally create a power point display and put up the word, its different forms, its dictionary definition(s), and use it in a sentence. I also find some interesting or humorous pictures that can make them easier to understand. I make sure I have the phonetic pronunciation included as well. As I go through the PPT, students are encouraged to take notes, copy sentences, jot down the Chinese translation, anything that will help them understand it better. This gives them something tangible to do as opposed to just listening to you talk about their meanings and what-not.
Then I would have them get together in small groups and hammer out a story or a dialogue or something that uses most, if not all, of the vocabulary words for that unit. Don't forget to explore word origins, synonyms, antonyms, homophones, base words, etc. to give them a fuller understanding. Also, getting them to learn how to pronounce the words correctly can take a bit of time. There's nothing wrong with creating work sheets with fill-in-the-blank, matching, multiple choice, and so on (of course, their workbooks may have plenty of these exercises - - can you make them simpler?). They can do these on their own time or as group activities in class (One favorite thing I like to do is have them try to do a worksheet on their own and then, when they finish, find someone else who is also finished and compare their answers. If they disagree, have them discuss it IN ENGLISH and come to a conclusion as to who may be correct and who may be incorrect. Then of course, share answers with the rest of the class.). Playing charades with some of the words is a fun way to get them to try and figure them out and see if the charade actor truly understands the meaning.
As for slang terms like "wax euphoric", go back to what it means using descriptions and vocabulary they can understand: to grow in the feeling of happiness about something or someone. Example: The teacher waxed euphoric about his favorite student, although I didn't feel like I deserved so many compliments.
Adjectives (such as elusive) and adverbs, conjunctions, prepositions, and so on are a bit trickier, but using as many different ways to make them understand the words by definitions, actions, pictures, examples, will go a long way. Do a google search for online dictionaries. Some of these web pages may have even more suggestions. Good luck!