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