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