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