First, find a good picture of the celebrity, person or cartoon character you want to imitate.
Then reset your medoll to a basic face and add any jewelry you may need for the look, like Marilyn's beauty mark.
Now, pick the hair you want for the look. I put up a superstar and non superstar option.
Next change the face shape to one that looks like your person.
Change the eyes and their color. To figure out the right eyes, consider your person's ethnicity, how deep set their eyes are and what mood they put off.
Next change the lips. Think about the mood they put out and the expression on their face most of the time.
Last, do the eyebrows.
Do the makeup in the person's everyday style.
Just to show how this works, I did Robecca steam from that new campaign stardoll's doing, Monster High.
Rochelle Goyle, as well.
And just to top it off, Venus McFlytrap.
I hope you find this useful!