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