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