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)(11,21)(12,17)(13,20)(14,18)(15,19)(16,23)(22,36)(24,33)(25,34)(26,32)(27,30)(28,31)(29,38)(35,39)(37,40)(1,3)(2,5)(4,7)(6,8)(9,11)(10,16)(12,22)(13,23)(14,27)(15,24)(17,29)(18,21)(19,30)(20,33)(25,37)(26,39)(28,38)(31,35)(32,40)(34,36) involution — undirected(3,7)(5,8)(9,12,15,26)(10,17,19,32)(11,22,24,39)(13,25,14,28)(16,29,30,40)(18,31,20,34)(21,35,33,36)(23,37,27,38)(1,3)(2,5)(4,7)(6,8)(9,13,15,14)(10,18,19,20)(11,23,24,27)(12,25,26,28)(16,21,30,33)(17,31,32,34)(22,37,39,38)(29,35,40,36)(3,7)(5,8)(10,19)(16,30)(17,32)(18,20)(21,33)(29,40)(31,34)(35,36) 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.