Diego, I prepared a detailed procedure to install osmc on my Raspberry Pi 3, replete with screen snaps to illustrate the written instructions. I would be happy to email you a copy. I could post here as a pdf file if I knew that was permitted and possible.
I can also extract the parts related to VNC setup and email (or post here, if permitted).
All my hardware is from Apple, from AirPort Extreme routers to MacBook Pros, so the instructions are very Apple-specific. My procedure requires no keyboard or monitor, just my Mac and the capabilities that are already part of MacOS.