Pictures are a simple, practical and highly effective way to teach English vocabulary. Cut out appropriate pictures from magazines and leaflets if you anticipate a word that will need explaining in class. For example, if teaching the word "beautiful", then bring two or three pictures of models to class. The more often you do this the bigger picture library you will acquire and this will make future class preparation much quicker and easier. For words that come up in class and for which you haven't prepared pictures, simply draw them, if possible, on the whiteboard.
Elicitation is a cornerstone of English language teaching and involves getting students to tell you the meaning of grammatical structures and words rather than you telling them. In this way you can be more sure of their understanding and more confident of their remembering it. For example, if teaching the present perfect tense, show or draw a picture of a man with a huge stomach, sitting at a dinner table and looking slightly ill. Ask the students, "How much did he eat?" "Does he feel good?" "Does he feel ill?" "Why does he feel ill?" Continue in this vein until a student produces the language, "He has eaten too much." You can now write the sentence on the board, highlight the structure and use a new picture to elicit another sentence in the present perfect.
Make ample use of synonyms when explaining new words or concepts. The chances are that students will understand one or more of the synonyms if you are teaching the correct level of language to your class. For example, if you are teaching the word "ordinary," you may choose to explain using the synonyms, "normal," "usual," "regular" and "everyday," and the antonyms, "unusual," "strange," "odd" and "extraordinary."
Exploit context to its fullest by showing students when and where a certain word might be appropriate. For example, if teaching the word "nervous," explain that this is something you might feel before an exam, when asking someone to marry you or before your first English class. Ask students to imagine how they feel when they have to speak before a large group of people or when walking down a dark street late at night. Most words become easier to explain within a proper context, so consider this when planning a lesson.