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