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