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