You should (by a should-be schedule):
Select wall.
Build your front room, or lounge/living room
Build the back room, or sun room (the reason for doing so is that you can make the rest of the rooms between)
Make the rooms in between (kitchen, dining, bedroom bathroom, etc, etc)
Do the wallpaper and floors
Add your objects
Might as well do the cheats if needed.
Chat with our AI personalities
you cannot build a 2 story house on sims 1
yes you can you just have to go to the gas station and enter a'm a idiot you can't
Unfortunately, you can't actually build stairs/upstairs for the sims on ps2 :'( get the sims 3 or the sims 2 (computer version(s)) to do this. Both work on pc, but only sims 3 works on mac :)
yes you just have to build it i think
in the sims 2 for the ps2 your sims can not have children