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