The Brew Potion feat states that:
You can create a potion of any 3rd-level or lower spell that you know and that targets one or more creatures or objects.
Does that includes spells with a personal range and you as the target, like for example Alter Self? Technically it targets "one creature" (you), but at the same time it's not exactly written "one creature" so I am not sure about it.
Best Answer
The Brew Potion feat allows a potion to be brewed of a spell that has an entry of Target: You, but not a potion of a spell that has an entry of Range: Personal. Creating Potions says pretty much exactly that: "Spells with a range of personal cannot be made into potions." Further, the description of Potions limits potions even more: A potion "can [only] duplicate the effect of a spell of up to 3rd level that has a casting time of less than 1 minute and targets one or more creatures or objects." Why all these rules aren't in one place is a mystery.
Thus it's typically impossible to brew, for example, a potion of alter self.