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