Humor can be an excellent way to capture the attention of students. One way in which humor is often used effectively is within anecdotal illustrations. If you have funny stories which you believe illustrate the point at hand, then by all means tell them. Of course, these stories shouldn't be your point, but they can be an effective way of recapturing the attention of your students, and of bringing the topic closer to home. Another valuable use of humor in teaching, is to laugh at yourself.
All teachers make mistakes.
Those that can see the humor in what they've done can both put the students at ease and maintain their own composure and confidence. Often, students report that rather than the accent being the biggest frustration, it is the lack of auditory comprehension of English by teachers for whom English is their second language. That is, it is very frustrating to students when the teacher does not understand their questions, and, nevertheless, makes a stab at an answer to a completely different question. Make sure that you understand your students' questions before you answer them. This may mean asking them to repeat their questions in simpler, less colloquial English.