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