There are products that I have loved having in my closet and they maximize storage space! One is a sandal holder. They aren't expensive to buy and are perfect for dorms. Add it to your list like now cause it is so worth it!
The Sandal Rack I have is pictured below, it's $9.99 at Bed, Bath, and Beyond. Heres the link! I love it because it is really thin and fits in my closet nice without being tacky like other shoe holders. It hangs on a normal rack like regualr hanger. The clips have fit almost all of my sandals not just flip flops like in the picture.