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