First of all, I don't recommend using an RBA on an eGo class battery. They do not have the amperage required to safely use one. You should consider getting either a mechanical, or better yet, a regulated V-V/V-W mod, that uses replaceable, rechargeable batteries.
Don't skimp on battery quality, use either AW or Panasonic IMR batteries. I also suggest using a Vape Safe or 2 Cent mod fuse. The more layers of safey you have the better.
Batteries : Vape Safe Mod Fuse 2
You will need a way to measure the resistance of the coils that you make. I suggest getting a digital multimeter, or if your mod has a built-in atomizer meter that will suffice.
A minature butane torch is useful to oxidize your stainless steel mesh and wire.
Of course you'll need to purchase stainless steel mesh and some wire. I recommend getting two or three gauges of wire to see which you prefer for the coil that you will use for your RBA and whether you will be using a mechanical or regulated mod. The mesh and wire that comes in the kits are often inadequate or of poor quality, so order some when you order your RBA.
I've written a starter's guide for vapors considering their first RBA. It's not specifically a tutorial, but an information resource guide to educate yourself for the safe use of an RBA:
http://www.e-cigarette-forum.com/forum/blogs/baditude/4454-7-advice-tips-vapors-looking-try-their-first-rba.html