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