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