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The Sims has a Create-a-Sim mode that is fairly simple.

[edit] How to get there

Go to the neighborhood menu. In the uppermost portion of the screen there are three buttons. The first button will bring up a list of families already created. To create a new family, click on the button of three people with a plus sign at the bottom of the screen.

[edit] Creating a Sim family

To add new members to the family click on the button that is a picture of a person with a plus sign. You may change the look of your Sim, including the skin tone, hair color, clothing, etc. You may also enter a bio for the Sim, though this is not required. When you are done click the OK button. A message will pop up asking whether you are sure you wish to create this family. If you accept, you will not be able to modify them again.

[edit] The family is ready to move

After, you will be back to the family screen with the family you just created. Press the button with an arrow pointing to a house. You will then be returned to the neighborhood screen with the cursor like 3 people. Choose a lot or house and click on it. It will load up that lot along with your new family. Now you can build the house and buy things for the family.