Jack up and secure the car with jack stands and then remove the tire for the sensor you wish to test.
Turning the front wheel makes it easier to get at the sensor plug.
Making a testing pig tail is the best way to go about this. You simply need a old plug. I took a plug from a old hub, and then bought a new plug for the other side and put a spade connector in the middle so I can clip on my leads. This way I can test both sides, or even test with the sensors while in operation.
Plug in the pig tail so only the sensor is plugged in. Then hook up your DVOM and set it to Ohms. You should see 850 to 1350 ohms on the meter display. If you don't, replace the sensor, it'* trash. If the resistance is within this range, try manipulating or bending the wires while you watch the meter display. If the resistance goes out of range, you're dealing with an intermittent in the wiring. Replace the wheel speed sensor.
This shows a failed WSS
Next test is to check for a short. Connect the ground of your DVOM to a good ground and set the DVOM to check resistance. You should show infinity.
Now switch to the other lead and do the same test, again, you should show infinity.
Next test is to check for voltage. Set your DVOM to check up to 100mv. connect to both sensor wires, and spin the wheel. The voltage should go up and down. Voltage moving up and down shows a good sensor.
If you have a lab scope, it will look like this. You can see the voltage going up and down.