One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,12)(4,9)(5,8)(6,15)(7,11)(10,13)(14,16)(17,18)(19,25)(20,28)(21,24)(22,27)(23,29)(26,32)(30,31) involution — undirected(1,3,7,13)(2,8,11,16)(4,5,6,14)(9,10,15,12)(20,29)(22,31)(23,28)(27,30)(1,4,7,6)(2,9,11,15)(3,5,13,14)(8,10,16,12)(17,19,21,26)(18,22,24,31)(20,30,29,27)(23,32,28,25)(1,5,7,14)(2,10,11,12)(3,4,13,6)(8,9,16,15)(19,26)(22,31)(25,32)(27,30)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.