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