The Sims Tips

Perfect Personality
Create a sim with no personality points. Move the sim into a lot and buy a bunch of chemistry sets. Have your sim make potions until a yellow potion is created. Drink the potion and the sim will have maximum personality points for each personality trait.

This may take a while because the yellow potion is probably the least common potion that a sim can create. Have the sim drink every blue potion created because it helps its mood stay green, allowing it to make more potions.