How do you know how much to pursue?

Okay so I'm totally new to dating other women. I've been talking to this girl for a few weeks now online and then via text (we haven't gone out yet because of finals/the holidays taking up our time.) The thing is she always responds to my texts but she never texts me first... so I'm guessing she wants me to pursue her. I'm totally fine with that but I don't know how often is okay to text, etc. Right now I text her once every few days but I don't want her to think I'm losing interest, and at the same time I don't want to seem over-eager.

Is there some sort of a guideline as to how not to seem too overeager?

I would wait and give her a ring. That way, you should be able to tell if she likes you. She is playing the passive female role so far, so it is playing on your mind. A ring should give you more confidence if all is OK. But I would wait a while.

Texting can be a cold method of communication if that is the only thing you are doing.

I agree, cool it with the texting altogether, set up a coffee date or something. Face to face you can get a better sense of the person.