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