Wash your eggplant under cold water. You can use a vegetable spray or a mild soap. This is to get off all of the bacteria and dirt from the eggplant that might have gotten on them from the farm or from transport.
Trim your eggplant by simply cutting off the top and bottom. Cut the top off just under the leafy top. At the bottom cut off just where it starts to round. All you will cut from the bottom will be 1 inch.
Now that you are all trimmed up, go ahead and lay the eggplant horizontally in front of you. Cut across and all the way through every 1/4 inch or so. The size that you cut your rounds will depend on how thick you want them but I like them this thick.
Stack 2 or 3 rounds on top of each other and cut into 3rds or 4th across the eggplant. Then you want to turn your pile and cut again across the pile the same way you cut before, making them cross over the other cuts. The pieces will fall and you will have diced eggplant.
Cut the ends off, slice the eggplant in half and then cut wedges from the halves.