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