The picture below shows the sonar device pointing directly at the target. Here, two stacked weighted tubes are used as a target. Notice the fishing wire running from the tripod to the tubes. This fishing wire allows for aligning the device with the tubes. The wire also allows for keeping the distance to the tubes constant as you rotate the sonar device (see next image).

The picture below shows the sonar device rotated by about 30 degrees. Again, notice the fishing wire running from the tripod to the tubes.