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