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