Keep her in rotation. Call her once a week. Be brief but energetic with your messages and never acknowledge the fact that she hasn't returned nor picked up your phone.
Relationships get started with familiarity -- and quite frankly so does attraction. Also, be sure to work in calls on the weekday so that if you do happen to call on Friday/Sat it isn't awkward! Your intentions of meeting up are veiled by your other calls. It becomes a normality for her to receive your calls.
Also, be unpredictable (occassionally) with your initial message. Just recently I met a girl on St. Patty's day. I asked her several times to come out with a bunch of us. On third attempt (week 2), she responded "I'm in Dallas, TX." I responded "Come anyway

"
That Sunday I texted: "You better be bringing me back a cowboy hat." (Random)
Her: "What!? Why Would I? 11!1!"
Response: "Cause I would look damn good in one."
This led to other conversation, and it helps establish rapport, even though we've only met once.
Good luck!