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