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