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