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