Wiring security lights is necessary as they typically have no plug on them. They are designed for hard wiring into the electrical system. Fortunately, security lights are usually simpler to wire than other light wiring projects since no switch is needed. You can do this fairly quickly and avoiding spending big money on an electrician. Security lights go on and off automatically by motion sensor, or if you are not getting this type, they are photo cell, meaning off during the day, on at night. With motion sensor lights you can set the sensitivity, and time duration of the on time.
Turn off the electricity at the main breaker to the entire house.
Run the wire through the hole that is cut for your light, and strip 1 inch off the electrical wire, and attach the wires to your security light, matching colours. Ground wire will always be screwed on to the green screw of the base of the fixture. Screw up your light.
Go to the nearest outlet and remove the faceplate from the outlet and unscrew the outlet. Run your wire in the wall to your outlet. Cut to length.
Strip 1 inch off the wire, and attach the wires to the side screws of the outlet by matching colour.
Screw back the outlet, and faceplate. Turn on the electricity and test your work.