I know this sounds incredibly superficial, but wearing a striking piece of jewelry or a scarf, or something that is memorable without being weird can often help during a big-school rush. Even a bright-colored shell or sundress helps.
We didn't use photos or reccs during rush, and it became difficult. I lost two favorite rushees because X number of actives had to remember them, and not enough raised their hands to indicate that they remembered meeting them (one ended up COBing, thank goodness).
My ASA Little Sister wore a Mickey Mouse watch with a head that nodded. This may not have gone over at some of the more sophisticated sororities, but it worked with the us, (we tended to be a little more whimsical). She was not a conventionally attractive girl, but amazingly funny and full of energy. Not everyone remembered "Joann" but the minute someone said "the girl with the Mickey Mouse watch" every hand went up (it also helped that it worked with her personality).
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