Learning alchemy can be broken down to 3 different parts.
Remember, you can only learn as many spells as your int mod. Previous spells can be unlearned at any time, but if you want them back you need to relearn them once more with a DM.
Part 1) Study
To cast an alchemy spell, one must first understand it completely. This is done via study. This is a d20+lore v.s the learn dc of the spell. This may only be attempted once per day, and a dm is needed to witness the roll.
Part 2) Gathering Basic Materials
The second part of the training is to gather the basic materials for the spell. This is d20+spellcraft vs learn dc. This may be attempted once per day. A dm is needed to witness the roll.
Part 3) Practice!
The third part of the training is practice and concentration. This is done with d20+concentration v.s learn dc. Upon success of this roll, the spell is then acquired. This can be attempted once per day. A Dm is needed to witness the roll.
To create a new spell, the same steps as above must be done. However, the spell must be approved ahead of time. As well, the creator of the spell will have a +20 DC to the learn dc, because he or she is the first to ever create the spell.
Creating Gold is forbidden. And It's forbidden in the server too..sorry. =P Alchemists can't create gold. Even the evil people are going to need to find justification why they don't believe in creating gold, because it's an OOC rule that you can't. (Unless you earn your gold legitly, and just rp that you created it. That would be acceptable.)
Human Transmutation is forbidden IC. And one of the quickest ways to get your character in deep doo-doo. It is also extremely difficult. See separate post for human transmutation.