Is it a good idea to try to talk to this girl online? How?

so i really like a girl and we are familiar with each other because we see each other around campus but don't really know each other. but i REALLY need to step it up because it's difficult to talk to her and i've been stalling. i asked her out to lunch a week ago but we left it up in the air because of midterms. we're friends on facebook and i want to talk to her. but she's not on chat much so should i send her a message, and just say hey how's your break going? and then ask if she'd like to talk on skype or something?