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