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