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