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