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