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