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