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