With a bit of upfront time investment, and luck, you can kickstart your transmog business. What I recommend is to spend 6-8 hours, or however many you can stomach, farming ZF, WC, and RFK over the course of a week. This should net you a few hundred items of value to list on the AH. Over the coming weeks and months, spend at least one hour per week, revisiting one of these dungeons, or branch out into other classic dungeons.
Professions are skills used to create and enhance items (gears). You will start with one skill once your character has learned a profession. When you use the profession, your skill will increase. A profession’s higher skill will allow you to create more powerful items. If you change a primary profession, you will lose any skill you have made with your original profession. So it is important to choose your primary professions wisely.
Set sail for the previously unmapped isles of Azeroth. Battle in groups of three as you race against cunning rival intruders—or enemy players—to collect the island’s resources. Constantly evolving challenges await as you traverse frozen landscapes near Northrend, open the mysterious gates of an abandoned Gilnean castle, navigate a war between elementals and more.
I highly recommend actually staying in the 20-60 range zones until you ding 62. The reason for this is that despite getting a slight penalty in experience for being over-level, the advantage of having flight will more than offset this. That, and WOTLK and TBC zones are the slowest part of the leveling process. Minimizing your time there as much as possible is worthwhile.
First of all, the value of transmog is decided by rarity and how they look. Some items like Minenarbeithut der Tiefen or Pendel der Verdammnis (they can drop in Uldaman) are worth millions of gold. They are worth so much, because they have a really small chance to drop. Other items are bought well because they look good. Best example in this case is the Glorious set, its legplates Glorreichen Beinplatte reach a 100.000 Gold value easily.