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