Open up the Inspector tool (house with a magnifying glass on it, press
).
Zoom in using
until you can see people walking around on your streets, tap
on a person to bring up an information box in the corner.
Press
on the green arrow button to have the camera follow the person.
Go right twice on the D-Pad to the "Toggle Traffic Routes View" and press
. The world should go grey and bring up a green line showing where they're going.
Achievement should pop shortly after