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