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