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