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