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