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