Welcome to cc, Miafia! I'm sure you will get all the help you need here.
A high heel shoe on a colorful dance floor like in Saturday Night Fever. My brain isn't in gear for it now; but you might find lyrics to a disco song that speak of being on your own, or being grown up, or 'making it".
I don't know if this will help, but I had to do a graduation cake with a Hip-Hop dancer theme. I had edible pictures printed up of hip-hop dancers in silhouettes and placed them on fondant before placed them on the side of the cake. You could use the silhouettes of these disco dancers with the wild strips all over the cake like on the plate. And what about a disco ball as the topper with a graduation cap? HTH
Silhouettes example of Disco dancers. If you click on the plate, you'll get a larger image.
http://images.google.com/imgres?imgurl=http://images.buycostumes.com/mgen/merchandiser/24349.jpg&imgrefurl=http://www.costumes-accessories-props-more.age2shop.com/143919.html&usg=__7wyD4fo6aecnbkhY40VCU-XS2So=&h=898&w=898&sz=127&hl=en&start=14&um=1&tbnid=mzq8p1AeX9MpUM:&tbnh=146&tbnw=146&prev=/images%3Fq%3Ddisco%2Bcake%2Bideas%26hl%3Den%26rlz%3D1T4GWYE_enUS312US312%26sa%3DN%26um%3D1
http://www.google.com/imgres?imgurl=http://www.featurepics.com/FI/Thumb/20070208/Silhouettes-Dancing-Girls-213979.jpg&imgrefurl=http://www.featurepics.com/selections/People-Silhouettes-49.htm&h=130&w=130&sz=7&tbnid=IqB-vLxDpwRGWM::&tbnh=91&tbnw=91&prev=/images%3Fq%3Ddisco%2BSilhouettes&usg=__STiBcWHS2dXYAvd5Medp3U9nK-o=&ei=OFG0Sdz6OeCbtweM_vnEBw&sa=X&oi=image_result&resnum=2&ct=image&cd=1
Here is the picture of my hip hop cake
www.cakecentral.com/modules.php?name=gallery&file=displayimage&pid=1305594
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