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