Read the guides in the Maximus section, even the older guides in the archive are worth reading. Does not matter if your board is different as the bios layout is the same. And then read them again. Get to know what your bios set up is like before you actually start playing.
What can go wrong - you can kill your hardware. Sorry but that can happen if you carry your hardware in a box and drop it too.
We overclock because we can.
It works immediately your system is in OS and or you press F10 and enter after changing something in bios.
Yes it is easy if you take it slow and do not over complicate things. You only need to change 4 settings at the end of the day. Mode of OC to XMP, the multi, your LLC to medium and the vcore.
The rest just leave at auto.
To help us help you - please provide as much information about your system and the problem as possible.