The idea is based on OSRS gold the notion that when you know the precise number of doors in each space within the construction skill, and you can draw it out on paper or on the screen of your computer, it's simpler to create an attractive design for your POH.
It is a file that can be downloaded and then opened by opening it in Windows Paint (or another similar software) to play around with using your computer. Print it out and cut out the squares or cut them out by hand. There are many rooms that you can use, and you may require copying and pasting or print multiple copies to get the desired result.
I am currently in the 50th level of construction and I haven't yet built an Dungeon. Let me know if there were any mistakes when setting the doors in the two rooms with doors in the dungeon. I wasn't certain whether the doors were close to one another or across.
Here's an illustration of the layout I designed for my second and first floors: It is a representation of all of the Chapels. My personal favorite is Guthix's Chapel that is on the second floor of buy RS gold my "Royal Suite". I have four rooms that I can create an Dungeon in the event that I would like one. Maybe I'll reconsider my decision in the future however, this is the current plan I have for my RS "dream home".