Turn off the electrical power. Do this by checking the fuse box, which is usually located in the basement. If the place doesn't have a basement, then it may be located in a closet. In the fuse box there are several switches that will go to each room and one overall switch for power. If you are uncertain, then flip all of them off.
Determine where to hang the chandelier. Most chandeliers are hung in dining rooms. It would have to be at least 2 feet and 6 inches above the table in order to prevent people from bumping their heads on it. The chandelier shouldn't be any wider than 12 inches from the ends of the table.
Disconnect the cover to the original light fixture. See how the wires are attached. Match the wires up with the chandelier. Remove the light fixture and connect chandelier wires. Connect the white wires from the chandelier to the white wires in the ceiling and do the same with the black wires.
Connect an electrical box if there is not one attached already. This will be braced in the ceiling where the old fixture was. If you are putting a chandelier where there isn't a fixture then you may need an electrical box put in. Draw a circle where the chandelier will hang. Cut the circle out with a drywall saw. Fit an expandable bracket into the hole and place it horizontally between two ceiling joists. Turn the bracket and it will expand to fit tightly in the joists.
Use a small U shaped bracket to fit on top of the expandable bracket. The small bracket will have two screws on each side to be screwed into the electrical box. Put the electrical box through the hole in the ceiling and tighten the screws to keep the box in place. Use a knife to strip about an inch of insulation off the wires and twist same colored wires together. Connect them with a wire nut to keep them together.