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