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