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