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