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