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)(25,26,29,33,30,34,38,31)(27,35,37,39,36,32,40,28)(1,3,4,7)(2,5,6,8)(9,11)(10,14)(12,19)(13,18)(15,23)(16,22)(17,20)(21,24)(26,31)(28,35)(29,38)(32,39)(33,34)(37,40)(2,6)(5,8)(9,12)(10,15)(11,17)(13,20)(14,21)(16,24)(18,19)(22,23)(25,27,30,36)(26,32,34,35)(28,31,39,33)(29,37,38,40)(12,20)(15,24)(17,19)(21,23)(25,28,38,32,30,39,29,35)(26,27,31,40,34,36,33,37)(10,16)(11,18)(15,24)(17,19)(27,36)(28,39)(32,35)(37,40) 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.