Texting seems to be the way more girls these days are into communicating. They pick up their phones less and less.
Do not wait weeks to contact her. A few days at most.
Do not try to establish comfort or rapport via text. Use it to set up a meet.
When setting up a meet, tell her what you are doing and suggest she should join. Don't ask her out on a formal date for the first meet up.
"Heading out to XYZ for happy hour. Great drinks here. You should come join."
"Hanging out a [coffee shop] for a few. Come hang for a while."
"Going to XYZ for lunch. Great food, you'd like it."
And so on.
NOTHING LIKE THIS: "What you doing?" "How's your day?" Etc.
If she doesn't respond, move on.
If she does respond and says she can't, then see if she suggests another time. It still might work out.
If she doesn't suggest another time/place, her interest level is low. Game other chicks until she contacts you.