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