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