Put on work boots with non-slip soles to avoid slipping on the roof. Wear work gloves with rubber grips as well so you can securely grip the hand tools. Position a ladder next to the roof in an area as close to the ice dam as possible.
Shovel off all of the fresh snow on top of the roof dam and toss it onto the ground. Only shovel until you expose the underlying ice dam.
Walk to the top of the roof to begin removing the ice dam. Never start at the bottom of the roof since the ice can break off and create a slipping hazard.
Tap the ice gently but firmly with a rubber mallet and start working your way from the edge of the ice dam toward the center to break it up. If the mallet does not crack the ice, use a standard hammer or even a 3-pound sledgehammer for thicker accumulations of ice.
Continue breaking up the ice while working your way downward until the roof is completely free of ice.