Answer:
Once when preparing for a Spanish test I used repetition to help me study. This technique was useful for me, because when I wrote out vocabulary words and continued to review them until the day of the test it helped me remember the words a lot easier.
Three shots, three blasts on a whistle, three flashes with a mirror, or three fires evenly spaced. If you're near an open space, walk an "X" in the snow, grass, or sand