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