Communication was a bussiness one should go about very carefully in the Victorian Era, something you might be aware of it you played the Victorian etiquette game I linked you to earlier. Here are some more ways to let people know what you mean without offending them, if you find yourself all of a sudden in the nineteenth century.
Communicating with flowers: Did you know you shouldn’t give your love a yellow rose? It might be seen as a sign of jealousy. The language of flowers is very delicate, because you want to pick the absolute right flower to convey your message. Here is a Livejournal group that can tell you more.
Want to tell your beaux to not flirt with that woman, without letting everyone know? It’s as easy as fanning yourself with your left hand. I think it’s a pretty hard language to learn, but who knows, it might be worth it: The language of the fan.
Calling cards are both communication, and not really communication. Leaving a calling card will show your politeness and that you’re aware of the social mores, without having to actually talk to anyone. Perfect, I’d say. There’s quite some etiquette surrounding calling cards, you can find out more here and here.
Don’t forget, if someone leaves you a calling card, you are obliged to go over and return the favour, or you might find yourself to be the subject of quite some gossip!