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