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