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