First I would definitely talk to your advisor (chapter or regional, whatever terms they go by) for help with making a plan for your school's recruitment. Every school is extremely different in what methods work best for them and what works for your individual chapter, so be sure to use her as a resource.
Second, one method of "recruitment" that I see as fail safe and cost free is constantly representing yourself in a positive light. Make sure that you are reaching out to great women across campus through other extracurriculars and classes. Be kind to women, take an interest in them. Don't try to sell sorority life, but show them through your actions what it can be. Keep your academic standards high. Work on your chapter's sisterhood. Befriend every type of woman and man (they have girl friends and girlfriends too, you know) and be yourselves. It's the simplest and best way to recruit new members, period. And best of all it's free.
One thing that has worked for my organization (and I've mentioned this before so forgive me for repeating myself) is doing smaller, one or two people to the PNM "dates", where we do normal things (i.e. grab coffee or lunch) instead of bigger "recruitment/COB/COR parties". For us that works best because we shine best in a smaller setting, versus during formal recruitment it can be harder for us to stand out. Maybe the situation is similar for you, I'm not sure. Best of luck to you though, and congratulations on Phi Sigma Sigma and becoming recruitment chair!
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