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