I was at the top of Snowdon one morning..,
No particular skill to this ... Just be there and not afraid to reduce the exposure to keep the darkness and the colours of the sunrise.
Most cameras will over lighten such pictures - the +-ev button is your biggest friend when it comes to taking picture. Some consider it a blunt instrument and there is a whole raft of discussion on the photo forums on the internet on whether you should use it because there may be a few pixels clipped.
My opinion is I can afford to clip a few in a 12Mp image as long as they are not the important ones