Use the line sensor #3, #4, and #5 to steer the robot and follow the line.
Sensor #3 - Robot Sharp Left
Sensor #4 - Robot go Forward
Sensor #5 - Robot Sharp Right
Add in line sensor #2 and #4 to steer the robot and follow the line.
Sensor #2 - Robot Sharp Left
Sensor #3 - Robot Turn slightly Left
Sensor #4 - Robot go Forward
Sensor #5 - Robot Turn slightly Right
Sensor #6 - Robot Sharp Right