All good advice, but I believe
anybody can learn to be a good recruiter. It does, however, take some practice, and you can do that with other sisters, "swapping" with a nearby chapter or even another sorority on campus...or just practice a bit in everyday conversations.
What you're practicing is getting to know somebody you've never met before. Skills that are handy throughout life.
A few tips: relax, prepare mentally by telling yourself this is fun and keeping a list of topics in mind, practice with a respondent who has 1-syllable answers, forget about yourself and concentrate on the other person.
I
highly, highly recommend reading the old classic, "How to Win Friends and Influence People." Several here have recommended "I Heart Recruitment." Barbara Walters had a good book out (probably out of print - check used paperback bookstores or amazon.com), "How to Talk to Practically Anybody About Practically Anything."
Good luck to you!!