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