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