1 Answer

Things You'll Need
Transfer switch
Electrical cable
Hacksaw
Wire strippers
Allen wrench
Electric generator

Instructions
1
Start the installation by disconnecting the incoming electric cables inside the breaker box. The power should be off at the electric meter before attempting to work inside the breaker panel. Use an Allen wrench to loosen the lugs on the main breaker to release the two cables that are attached. Use the wrench to disconnect the white cable running to the lug on the neutral bus. Pull all three wires from the box.

2
Attach the transfer switch using screws and a cordless electric screwdriver to a location near the main breaker panel. Feed the cables from the electric meter into the transfer switch box. The ends of two black power cables will be pushed beneath the two lugs at the top of the box. Use the Allen wrench to tighten the lugs down onto the wires. The white or ground wire will pass through the transfer switch box and into the breaker panel.

3
Feed the two hot wires and one ground wire from the generator into the lower portion of the transfer switch box. The two black or one black and one red cables are inserted into the lugs in the bottom half of the box. Tighten the lugs to secure the wires. The ground wire will pass through the box and into the breaker panel.

4
Cut two pieces of electric cable long enough to reach from the center of the transfer switch to the lugs on the main breaker in the breaker box. You will probably need to use a hacksaw to cut this cable. With wire strippers remove about one inch of insulation from each end of both wires. One end of each wire will be pushed under the two lugs in the center of the transfer switch. The other two will pass into the breaker box and be attached to the main breaker lugs. Both ground cables will go under the lug on the neutral bus. Secure all wires by tightening the lugs with the Allen wrench.

5
Place the transfer switch in the middle or "off" position. Turn the power on at the electric meter. Push the transfer switch to the position that engages the utility power. When the main breaker is on, the house power should now be restored. To test the generator, start the generator. When it is at full power, move the transfer switch to "off" and then to the generator position to power the house. When the test is completed, restore the transfer switch to utility power and shut down the generator. 

http://www.ehow.com/how_7761335_connect-generator-circuit-breaker-box.html