Unplug the dryer before servicing it to prevent serious electrical injury. Close the gas valve to disrupt the gas supply to the appliance.
Locate the lint trap assembly on the top of the dryer. Lift the lint trap cover, and take out the lint screen. Use a flat-head screwdriver to remove the two screws on the lint trap housing. Set aside the removed components.
Run the flat-head screwdriver along the bottom edge of the top panel to find the metal clips that secure the panel to the dryer cabinet. Apply pressure to the clips with the tip of the screwdriver to release them. Lift the top panel up, and lean it back against the wall.
Remove the screws along the top and bottom edges of the front panel. Pull the front panel away from the cabinet, and set it aside with the removed screws.
Discard the worn or broken dryer belt. Slip the replacement belt over the drum with the ribbed side facing down. Guide the belt into the belt track.
Locate the idler assembly on the left side of the dryer cabinet, below the drum. Pull the idler pulley to the left, and hook the belt on the adjacent motor pulley. Release the idler pulley to set the belt tension.