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