One vertex per element, one color per generator, with an edge from x to x·s.
(2,7)(3,10)(4,5)(9,12)(11,13)(14,15)(18,22)(20,27)(23,31)(24,28)(25,29)(30,32) involution — undirected(1,2)(3,8)(4,12)(5,7)(6,9)(10,15)(11,16)(13,14)(17,18,21,24)(19,23,26,32)(20,28,27,22)(25,30,29,31)(1,3,6,11)(2,8,9,16)(4,10,5,13)(7,14,12,15)(17,19,21,26)(18,23,24,32)(20,29,27,25)(22,30,28,31)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.