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