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