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