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