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