Well, everybody knows how to do it, cut a strip, twist and glue. But what should be the size of the strip? Believe or not, it is not known. We will discuss this and related problems. Be prepared to do some gluing work with your skillful hands. See you there.
Additionally, I found a very nice interactive website on Moebius band:
Interactive Graphics: Moebius Band
Moebius Band in R^3 with one twist
Moebius Band in R^3 with three twists