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