I run into this problem fairly often -- for instance when teaching slope, I want to impress upon the students that if the slope is positive, the graph gets higher as you scan from right to left. I found myself gesturing from left to right; but it was my left, so the students were seeing right-to-left motion.
Now I often write in "stage direction" into my notes -- reminders that, in theatrical terms, house left=stage right. This way I remember to reverse the directions so the students see a consistent message.
I do not encounter the same problem with direction (i.e. North, South, East, and West) as all in the room will agree.