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