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