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