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)(13,14,16,19)(15,18,20,17)(22,23)(24,28)(6,9)(10,11)(13,15)(14,17)(16,20)(18,19)(22,23)(26,27) involution — undirected(7,12)(10,11)(15,20)(17,18)(21,22,25,23)(24,26,28,27)(1,2,3,4)(5,7,8,12)(6,10,9,11)(13,15)(14,18)(16,20)(17,19)(21,23,25,22)(24,27,28,26)(5,6)(7,10)(8,9)(11,12)(13,14)(15,18)(16,19)(17,20)(21,24)(22,26)(23,27)(25,28) 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.