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