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