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