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