This is the section I would have wanted to find when I was where you are now. The tactical, practical, here-is-what-to-actually-do part. None of this is in the conventional rush advice posts because the people writing those posts assume you already know it.
Vocabulary catch-up is normal
You are going to be playing vocabulary catch-up for your entire first semester, and that is normal. The chapter will have its own language. Officer titles, traditions, weekly meeting structures, terms for the freshman class versus the active members. Do not panic when you do not understand half of what is said in your first new member meeting. By month three you will be fluent. Ask questions. Your big will explain things. Most new members are catching up on something, even if they came from a Greek family, so you are less of an outlier than you think.
Get your application and resume right before recruitment
Chapters look at applications, and at the bigger schools they make decisions in about thirty seconds per girl. Once you submit, you cannot edit it. This is the place where a first-gen disadvantage shows up most concretely, because legacy girls usually have a mom or a sister helping them polish theirs. If you do not have that person, get it polished anyway. The Application Playbook exists for exactly this.
Rec letters work differently than you think
If you are going to a school where fewer than three or four hundred girls are rushing, you probably do not need them. If you are going to a school where over a thousand girls are rushing, you should have them. Ask around at your job, at your parents’ jobs, at family friends. People you know may be Greek and have never mentioned it. If you cannot find anyone, the bigger national sororities have introduce-yourself forms on their websites that function as rec letters you can fill out yourself. Use them. They are free, and they are the workaround nobody mentions.
The costume thing is a real expense if you are not prepared
Sororities have a lot of themed events. Some are required, some are optional, and almost all of them ask you to dress a specific way. Here is what you do. You build a small base wardrobe of versatile pieces, and then you borrow. The borrowing economy inside a sorority is one of its actual best features. Sisters lend each other dresses, tops, shoes, jewelry, costume pieces. You will rewear a formal dress more than once and nobody will care. You do not need a new wardrobe to walk into recruitment week and you do not need twelve costume options to walk into your first semester. You need to make friends with the size-similar girls in your chapter, and the closet expands on its own.
When you don’t know something, ask
This is the biggest tactical difference between first-gen new members and legacy new members. Legacy girls have been quietly absorbing answers their whole lives, so they ask fewer questions out loud. First-gens sometimes think they need to fake fluency to fit in. Do not do that. Ask. Your big exists for exactly this. So does your new member educator. So do the seniors in your chapter who remember being lost too. You are not supposed to know everything yet. You are supposed to learn it.
Legacy girls have been absorbing answers their whole lives, so they ask fewer questions out loud. First-gens sometimes fake fluency to fit in. Don’t do that. Ask. Asking is the strategy.