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