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