Apart from vanity, there are good reasons to do so; some may recall me mentioning Wek at the end of Wrath and the start of Cataclysm. He achieved realm first Alchemist. His elixirs were much in demand, and more than paid for his skill leveling costs.
You need some things:
- 525 skill;
- on a level 85 toon.
- Probably a willingness to rush to level 89.
- Some farmers hooked up ahead of time.
- An idea of what recipes you will use, with the flexibility to cope with a lack of some mats.
The realm first seeker should read Kaliope's website. Kaliope is the best research site I know of for Beta tradeskills.
You need your gold stockpile. If Wek remembers right, he got his alchemy realm first for 15K; Speculatively, I would allow for at least 5 times as much as that.
Those farmers that you had lined up to gather for you will currently have good intentions. The road to hell is paved with good intentions. Bribe and remind; but accept that your farmers might be more interested in the new shiny expansion.
I normally would not consider it, but a second account or the remote auction house can keep an eye out for those missing mats while you are still questing.
Set your hearthstone appropriately. This should either be at an auction house capital city or where you are currently questing. You might still be able to use your teleport cloaks and have group will travel once MoP hits; but have a backup plan just in case Blizzard turns these off. Warlocks can summons; and Mages can teleport.
Have mats on hand for crafting out the last few points of yellow or green recipes for your existing 525 skills.
Can you get mats or recipes for any skillpoints ahead of time? The cooking dailies in the prequal to Cataclysm had some of these.
You needed to have level 84 toons to access some of the vendors and recipes. My recollection was that some of these were required to get to 525 skills. This kind of change can be tweaked by Blizzard with very little notice. Be prepared to level quickly (including flasks, potions and food).