I have several Female friends and I can say while I agree saying it straight away isn't very Manly but if after 5 months and you do love her just say it for the chances are her girl friends are bagging the crap out of you for not, sure it may scare her off, but if that's the case then you really don't have much of a relationship.
Women love talking about he holds my hand or how he touches me and o his sweet, yes a Women wants a Man not a Boy, but a true Man is a leader and a Leader is open about what he wants and if he loves a chick then that's what he wants, maybe its best if it comes in the form of a conversation about the world, but actions speak louder than words and if you really love her she will already know it