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