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