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