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