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