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