Shattering the Hourglass

You can alter your appearance to appear as any age.

Liber Mysterium
The Netbook of Witches and Warlocks  
By Timothy S. Brannan and The Netbook of Witches and Warlocks Team

Transmutation

Level: Witch 1
Components: V, S
Casting Time: 1 Action
Range: Personal
Target: You
Duration: 10 Minutes/Level

You incur normal aging penalties to physical ability scores but not to mental ones. If the age chosen is very different from your true age, it grants a +5 bonus to disguise checks.

Making yourself appear younger does not prolong your life, nor does making yourself appear older make you any closer to death.