Talk openly to students about cheating and also about plagiarism. Some students may be unclear about what constitutes cheating. Develop a good rapport with them. According to "Teaching Engineering," this significantly reduces cheating. Encourage good grades, but not to the exclusion of everything else. Also emphasize qualities such as integrity and honesty. Be approachable so students can feel free to talk to you. Cheating may relate to other problems in the student's life.
Reduce opportunities for cheating in the examination hall. Make sure all cell phones are kept outside of the room. See that all books and bags are out of reach. Observe the students closely and stand near a student you see acting suspiciously. Be familiar with all the different forms of cheating. These may range from looking at another student's work to hiding a cheat sheet.
Read the school's policy on cheating, which may include penalties ranging from a reduction in grade to expulsion. When you are sure that a student has cheated, document all the evidence carefully. Some schools may allow you to exercise discretion, but teachers should be careful when seeing a student on her own to discuss this issue, as he may later deny the conversation.