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