Place a ladder next to the roof and climb on the rooftop near the chimney.
Stretch a measuring tape out and insert it into the chimney. Have a helper inside the house at the fireplace. Insert the measuring tape to the helper inside and have him place the tip at the bottom of the chimney. Read the measurement at the top of the crown on the roof and add 18 inches to the measurement.
Put work gloves on. Lay the chimney flue liner flat on the ground. Cut the length of the liner to the measurement plus 18 inches with tin snips.
Place the bottom hose clamp on the bottom of the liner. Press the termination connector onto the liner and pull the hose clamp over it. Tighten the hose clamp worm screw with a screwdriver to hold the connector onto the liner. The termination connector connects to the top of a gas fireplace insert for ventilation.
Measure the diameter of the liner and multiply it by 3.14 (pi) to obtain the circumference of the liner. Add one inch to this measurement. Cut the flue insulation to the width of this measurement.
Lay the insulation on the ground with the foil side facing down. Set the liner in the center of the insulation. Wrap the insulation around the liner and tape it in place with foil tape over the 1-inch overlap.
Feed flue wire mesh over one end of the liner and pull it down to cover the entire liner and insulation.
Insert the top of the liner into the mounting bracket with anchors. Tighten the metal band with a screwdriver.
Cut a piece of rope about 1 foot longer than the flue liner. Tie a knot in the end of the rope and feed the free end through the pointed end of a nose cone from the inside. Press the nose cone on the bottom end of the liner and tape it on the bottom of the liner with duct tape. The rope will hang from the bottom of the nose come.
Climb the ladder to access the chimney top with the liner and rope. Push the rope down the chimney and push the liner down into the chimney. Have your helper inside the house pull the rope to help the liner go down the chimney.
Remove the tape on the nose cone and pull the rope out. Connect the bottom termination connector to the fireplace insert and tighten it with a screwdriver.
Screw the top anchors on the top mounting band to the top of the chimney to hold it in place.