To wear our country's flag properly, the field of stars is worn closest to your heart. Further, when worn on the sleeve of a military uniform, the flag should appear to be advancing and not retreating. Thus, if your patch is to be worn on your LEFT sleeve, use a left flag (normal). For patches worn on your RIGHT sleeve, use a "right" or "reversed field" flag.
http://www.ushistory.org/BETSY/flagetiq.html
(this was copird and pasted everyone else please feel free to do it too}