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