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