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