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