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