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