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