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