For what to serve, Venable suggests asking the graduate what she wants. The day is supposed to be about the student. Plus, chances are they aren't going to request an expensive meal -- they'll most likely want pizza or a taco bar.
Another area to trim costs is on decorations. Venable suggests not buying anything personalized. Instead, she recommends buying generic banners and then adding the graduate's name with construction paper cutouts.
She also recommends going with a theme other than the year. Venable tells her clients to "dare to be different," which can result in unique parties with unexpected themes, and it can also save money by buying decorations and accessories that can be used over again.