Build the moussaka from the bottom up:
PREPARE THE EGGPLANT
Wash the eggplants and trim off stems. Cut off 1/2-inch wide strips of the skin lengthwise, leaving about an inch in between, all around the eggplant, then cut the eggplant lengthwise into 1/2-inch slices.
Put the slices in a large bowl or on a tray, sprinkle liberally with salt and let them sit for 30 minutes. Rinse well, drain, and pat dry.
Brush slices lightly on both sides with olive oil and run them under the broiler on an ungreased cookie sheet until lightly browned and soft. Remove and set aside to cool.
Note: If you've never fixed this before, there are two reasons often given for salting the eggplant: (1) to remove any bitterness, and (2) to absorb some of the natural liquids.