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