Well it depends if you are talking about a motion sensor or a light sensor. A motion sensor turns the light on when there is movement and a light sensor turns the light off when there is enough light. If you want to turn the light off at any time just add the switch in series to one of the wires.Otherwise it can be more complicated.If you gave more information I can give better answers. :)
You should check out carefully that which type of switch is best suited here. And afterwards you can get it from the market there are different models and designs available for light sensor switches you can find them out in electrical stores easily. For more understanding you can check out the link given below:
I have just bought a sensor light to put in my garden, but I would also like to use this on a switch as a normal light but I'm unsure on how to wire it this way?
Well I am quite agree with kanza and will also tell you one more tip that try to find a socket with which you can connect more than one light sensor and then connect that socket in conduit. Secondly three phase light sensors are easily available. Take care