I've got a question since I'm completely newb in tech site of btc.
Lets assume that I want to rent a rig to mine one of the new coin. What do I have to do after I rent a rig? Register on pool which is mining the coin I've chosen?
You'll point the rig to a pool yes.
With a new coin with no pool, you need to be able point the rig to your pc, or your own personal server running the software.
If this is something you plan to do, be sure to test run before hand, and have a standard pool as a fallback.