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