Click [Ambition].
Click on the reward shop and drag down to find [Youth Potion] and drag down to find [Youth Potion].
Drag down to find [Youth Potion].
Click [Youth Potion].
The purchased potions will be in the [Purchase List].
Click on [Youth Potion] in your carry-on list and drink it.
After drinking [Youth Potion], the simulated character has become younger.
