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