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)(15,24,20,16)(17,22,27,26)(19,23,25,28)(5,7,8,12)(6,9,10,11)(13,15,18,20)(14,16,21,24)(17,19,27,25)(22,28,26,23)(1,2,3,4)(6,10)(7,12)(13,16,25,22,18,24,19,26)(14,20,28,17,21,15,23,27)(6,10)(9,11)(14,21)(16,24)(22,26)(23,28) involution — undirected(13,17,25,15,18,27,19,20)(14,22,28,24,21,26,23,16)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.