Helping students with vocabulary is really difficult but very important. Vocabulary is like the foundation of learning a language. However, it is a time-consuming and long-term work for each student.
Among various approaches teachers could use, I think appropriate context is the most helpful. With the help of context, it will be easier for learners to understand how to use the vocabulary and what the words really mean, compared with using translations and pictures.
When I was in college, my professor assigned a couple of readings or English movies every week. We were supposed to be familiar with all the words involved in those materials. We had an comprehensive exam in the next coming week. To score higher in the exam, we had to memorise all the unfamiliar words.
However, with the help of context, it was not difficult to memorise, neither easy to forget.