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