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