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