Upload code to Arduino and check results in Serial Monitor
How it's done
We described these two steps before.
Now, the results will be "0" or "1".
You can use potentiometer on sensor board to set sensor sensitivity, when will sensor switch value fomr "1" to "0".
In our case we set potentiometer to about 770 (analog read). We will read value "1" until value drops below 770. Then, the value will be "0" and additional LED on sensor board will turn on.
Don't forget that analog value starts from 1023 (when there is no water) and drop to nearly 200 when we put sensor in water.