One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,5)(4,6)(7,8)(9,10)(11,17)(12,15)(13,16)(14,19)(18,23)(20,22)(21,24)(25,26,30,31)(27,28,34,36)(29,37,38,32)(33,40,39,35)(1,3,4,7)(2,5,6,8)(9,11)(10,14)(12,18)(13,19)(15,21)(16,17)(20,24)(22,23)(25,27,30,34)(26,28,31,36)(29,35,38,40)(32,39,37,33)(2,6)(5,8)(9,12,13,20)(10,15,16,22)(11,18,19,24)(14,21,17,23)(25,28,31,34,30,36,26,27)(29,35,37,39,38,40,32,33)(10,16)(14,17)(15,22)(21,23)(29,38)(32,37)(33,39)(35,40) involution — undirected(11,19)(14,17)(18,24)(21,23)(25,29,26,32,30,38,31,37)(27,33,36,40,34,39,28,35)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.