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