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