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