In my experience tutoring students in both essay writing and test prep, one of the most difficult and tiresome challenges for both student and tutor is vocabulary improvement. Because the ideal way to improve one's vocabulary includes reading a variety of sources over a long period of time, the optimal strategy for vocabulary improvement is often not available to students who have a very compressed schedule in which they must improve. Many of my students have needed to show marked improvement in vocabulary within 2 weeks to a month, due to a looming deadline, so I have had to get creative to find efficient, effective techniques in vocabulary training.
One of the most important lessons when it comes to vocabulary is that multiple approaches are key. Students should engage with the material using as many senses as possible. This means not only reading a word and its definition silently, but also reading them aloud, hearing them read by someone else, writing the word and its definition out by hand, and reading it back. This repetitive process aids memorization by increasing the avenues of engagement with the student.
Another important note: vocabulary training can often become ineffectual due to cramming. More than most other subjects, vocabulary involves a lot of rote memorization, and is thus particularly susceptible to poor retention and confusion if it is rushed. It is essential that you ascertain that the student has really absorbed and comprehended the extant vocabulary words before moving on to study further. Oftentimes, the best approach is to break up a larger word list into smaller groups of 10-50 words (depending on list size, comprehension and time constraints) and make sure the student has fully retained each group of words before moving on to the next.
Vocabulary training can be challenging for students and tutors because it tends to involve repetitive, rote activities that can easily grow dull. It's therefore imperative that tutors make extra efforts to engage their students in the material using creative tactics to encourage active learning. Try thinking of outrageous or memorable examples for each word, and encourage your student to come up with his or her own examples (it is often easier for people to remember examples they have created themselves). Use Socratic teaching, when possible, to ask the student what possible root words, prefixes, and/or suffixes he or she can discern in the vocabulary words and how those might relate to the word's meaning. Ensure that your student understands the concept of connotation versus denotation, and include in your explanation of each word a discussion of its connotation as well as its literal meaning. Anything you do that enhances your student's understanding of the words and engages them intellectually will serve to further improve their retention and accuracy.
Do any other tutors or students have their own tips and tricks for teaching and learning vocabulary, or any questions about what I've mentioned? I'd be happy to hear.