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