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