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