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