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