Instructions
Enter a town and you will see three dots in the bottom left corner of the screen. Click the dots and a menu will appear. This is where you can save your game, change options and do many other things. Choose "Edit Town." You will be brought to a screen that is similar but has icons on top of the Lots.
Understand the difference in the icons above the lots. The empty square icons represent empty lots. Here you can start from scratch to build your own lot. The empty house icons represent lots that contain houses but no Sims. The house icon that is filled with white represents a lot that contains a house and Sims. The picnic bench icon represents a community lot like parks and schools. You cannot create your own lot sizes and locations like you could in "The Sims 2," but you can demolish previously built houses to build in current lots.
Click the empty lot icon. A box will pop up near the bottom right of the screen. This will indicate the size and address of the lot. You can choose to change the lot type to be community rather than residential, build/buy and edit the details of the lot. To start building, click "Build/Buy."
Click the empty house icon to edit a lot that contains a house but no Sims. A box will pop up in the bottom right of the screen that contains information with the address and size of the lot. There will be icons to change the lot type, save a copy to library, share, build/buy and edit details. Choose the fourth icon to start building. If you would like to demolish the house and start fresh, look at the bottom left of your screen and click the icon that looks like a bulldozer.
Click the white house icon to edit a lot that contains a house and Sims. A box will pop up in the bottom right of the screen that will show information about the Sims, the difficulty of the Sims, and the size and address of the lot. Icons at the bottom allow you to evict the Sim family, merge with another Sim family, split up household, save a copy to library, share and Edit details. To edit the lot, you will need to either begin playing with the current Sims in the household or evict the Sims. To evict the Sims, click the first icon that shows three Sims and an up arrow and choose to either "Move the Sims Out" or "Move the Sims Out With Home," causing the lot to be empty. Now you have a lot that is the same as one of the two previous steps.