Each dungeon starts out as 1 square, and is added to by rolling dice
To start, roll 1d8 to decide where to place the first section of tiles
|4|*|5| |6|7|8|
Once the orientation of the starting room has been rolled, roll 1d4 to decide the type of the starting room
1 | Corridor
2 | Room
3 | Hallway
4 |
Now roll to see how large the room will be, if it is a room, roll 1d20 to decide the height and roll another 1d20 for the width