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