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