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